I am in a new game going through the essentials kit at the moment.  I have played a lot of DND in past versions like 3.5 but not in 5th yet.  Because of the way my party is built,(druid, rouge, ranger/ranged, and divine Sorcerer) I am having to play the tank as a Warlock/hexblade.  I have a general idea what I want to do but had some questions and looking for general advice.  My DM let me use a homebrew feat that makes my shield my weapon.  Then gives me a weapon that can also add to my AC.  I am a Captain America fan as well.  I was thinking of taking Pact of the Blade but wonder if this is redundant with being a hexblade?  Should I consider another pact just to add some versatility to my character?  Any other tips would be appreciated.  Here is a link to my character:  https://www.dndbeyond.com/profile/Hylid/characters/15905606

Hexblade and pact of the Blade are not redundant, they're complementary.  Pact of the Blade allows you to access several melee/weapon-specific Invocations as well as granting you improvements to your Pact weapon, while hexblade gives you better armor proficiencies and the ability to attack with Charisma rather than Strength or Dexterity.  Pact of the Blade is the only way for a warlock to gain a second attack outside of two-weapon fighting or magic items (via the Thirsting Blade invocation), and without a second attack your shield punchery will fall off after fifth level.  It also gives you access to powerful burst damage in Eldritch Smite, which lets you turn a Pact Magic spell slot into a heavy-duty weapon hit.

HOWEVER.  Pact of The Tome also has applications for Hexbladfes.  If your DM allows it, you could opt for Booming Blade or Green Flame Blade on your shield, turning the one attack you get on your turn into an extra-powerful magical strike, and Pact of the Tome gives you access to extra cantrips to make that happen.  You also gain access to much stronger utility options from Pact of the Tome, between Aspect of the Moon removing the need for sleep and allowing you to take watch for your entire party all the time (as well as no-sell any sleeping drugs or magical sleep effects), and Book of Ancient Secrets allowing you the possibility of learning every single ritual spell in Fifth Edition if you're lucky and devoted enough.  A Hexblade warlock that opts for Pact of the Tome is playing up magical combat more than a Pact of the Blade type.

In summary: Blade gives you better attack options and burst damage, Tome gives you better magic.  I would avoid Chain on a Hexblade, especially one that's expecting to do a lot of heavy combat on the front lines.

Thank you.  I appreciate the feedback and will look into it more.  I do like the idea of keeping watch.  I should have mentioned that most of the party has not played DND before.  Here is the homebrew feat I made off an existing one that I am using for shield combat.  I could also make my shield my pact/hex weapon.  Also I love Green Flame Blade and my dm is ok with me using it.

Shield Fighter

You have spent years with fighting with your shield and you have learned how to use it to its furthest possibilities in defense. You have also learned how to cause the most damage to your victim when fight with your shield.

Shield of Pain:  Your shield does: 1d6 at 1st, 1d8 at 5th, 1d10 at 10th.  (Your shield is both considered a weapon and armor)

Shield Parry:  You can use your shields to parry and block incoming attacks. (Your shields now give you a +3 to your AC)

Don't over look Shield Master as a Feat, its a good way to get an extra attack option and the shield bonus to dex saves  is not to be sniffed at, also worth taking a look at the Charger feat for exta push/shove/damage and Martial Adept for a couple of Battlemaster maneuvers.

Re your shield fighter feat, what sort of damage type are you looking to inflict?The Targe is a historical shield with a spike on it so that could do piercing damage other wise you might have to do bludgeoning unless you can convince the DM to let you have a bladed edge to the shield to do slashing damage.

and can you dual wield a shield on each arm like a fire giant dreadnought? if you can, don't forget the Warcaster feat

Shield Master is good defensively, but doesn't provide an 'extra attack'; it lets you shove or trip as a bonus if you use a basic attack first, which conflicts with Green Flame Blade.  I'm assuming the shield damage is bludgeoning, and Charger is a trap.  Unless your DM fixes the feat somehow, Charger is pretty much strictly worse than not having Charger.

Dual shielding, on top of just being dumb in general, defeats one of the biggest strengths of his custom feat in that he doesn't need to use a weapon in his other hand.  He can keep it free for casting and avoid the War Caster feat tax, at least up until he starts needing that advantage on his concentration checks.  A free hand is a big edge I'd be hesitant to give up, especially as the AC bonus from shields doesn't stack.

The shield would be bludgeoning damage for sure and I am cool with that.  I considered take Pact of the Blade and then the invocation to improve the pact weapon so that my shield would then be my focus for casting spells.  Dual shields would be good if I could stack the AC but without that I can't see it giving me much other than flavor.  I have been looking at the defensive duelist feat so that I could use my reaction to add AC equal to my proficiency bonus then getting a rapier for the other hand.  That should let me case with my shield as the focus and use the sword if I want to without the need to take Warcaster. Unless I read that wrong.  So many things to research.  I do appreciate how versatile the Warlock is though. 

apologies, I thought I flagged this as a reply to Yurei1453 >

Maybe I should have worded it differently, instead of saying "an extra attack option" I should have said " a way of using your bonus action when you attack". Extra options can be useful, if you are trying to stealth in and knock some one over a cliff/parapet/roof etc then shield bashing would be better than a spell attack which won't force the target to move. Dual wielding  shields may sound like a dumb idea but given the fire giant dreadnought wields two shields and gets a AC bonus for both (although i think the second shield just gives 1 extra AC instead of 2), it was worth asking the question whether this was something that had been considered and a point of homebrew is to do things RAW don' allow/cater for. Additionally warcaster does give advantage on Cons saving throws which is useful for maintaining that hex or Blur spell whilst you're in melee, especially as Warlocks don't have proficiency with Cons saving throws.

**apologies I'm going off on a tangent re the charger feat**

As for charger, I don't understand the hate and trap conotations this feat gets, i agree to it being situational and if your combats always involve standing toe to toe with something and exchanging blows until one of you falls over or you are always guaranteed to be within a normal move of an opponent,  then yes, you may get more bang for your buck with another feat, but if you want to give yourself some mobility, especially if you only have one attack per round, then charger makes some sense, you move into range before your opponent is expecting you to, what if the big bad spell caster is 45 ft away from you and you only have 30ft of movement? Without charger you are stuck with dashing in and not hitting them or staying out of combat and letting them get an extra round to move/cast, charger would allow you to dash in and get into melee and hit them or shove them, what if you find yourself in a zone of silence?. In this type of situation your green flame blade/booming blades are useless. What if you have multiple opponents and they swarm past you to attack the squishy sorcerer in back? If the sorcerer is more than 30ft away form you then their in trouble until you can get back to them. What about dashing into someone else's melee and bashing their opponent out of melee range to provoke an attack of opportunity or bashing your friend out of melee? For me Charger is more about using combat and your action creatively, especially when the object may be to subdue your opponent not kill your opponent....a dominated party member would thank you for not killing them and just repeatedly shield bashing them back wards, especially if healing is low.

I honestly appreciate all feedback.  Even if the idea did not make since to me at first it gives me something to research and look into more.  If I could get an AC off the other shield and with that shield fighter feat make it a +2 to the second shield then it would be worth asking my DM about.  My DM allowed that feat because we realized I was the only character that had a chance to tank.  I am still not sure if that or defensive duelist would be better though.

I should just take 1 level of Warlock and then Pally the rest but I want a mostly Warlock character because I like the class.

No reason to take palladalladingdong levels if you don't want them.  A Hexblade can manage well enough if the DM lets it, especially with that feat of yours.  There's reasons to go either Blade or Tome for your pact, and since you're level 1, you've got some time to consider those options.

RE: Charger
Charger is a trap because it's hyperspecific and difficult to use.  You gain ONE THING you can do with Charger - make a swing or shove at the end of a Dash main-action Dash.  Rogues, which would otherwise be a natural choice for Charger due to only getting one high-value attack a turn, cannot make effective use of the feat because their dashes are bonus actions, not main actions.  Fighters give up one or more of their swings to get a Charger attack, barbarians and monks don't generally need the extra mobility.  A palladalladingdong might want the option to Smite something at the end of a dash, but palladalladingdongs can also fix their mobility issues by using a Find Steed spell and taking the much stronger (when mounted) Mounted Combatant feat.  Given that most characters will have the opportunity to make a Charger attack exactly once per combat, getting that single bonus action attack when you charge into the melee the first and only time you need to Dash on a typical battle map is not worth giving up all the other things you can do with an ASI.

Charger is a trap because it's overly specific, narrow, and limited.  Which suggests its fix, in a homebrew-friendly game.

I've got a revision for Charger I'm toying with in my own games which fixes the feat by splitting what it does into two separate, distinct abilities.  If you Dash as an action, you can make a single melee attack (which can be a shove, as per the normal attack rules) as a bonus action.  If you travel at least ten feet in a straight line before making an attack, then once per turn you can make it a Charger Strike that deals +5 damage, or shoves an extra ten feet, on a hit.  Notice that you no longer have to Dash to get the Charger attack (though your bonus action attack after a Dash can still be a Charger Strike), and normal battlefield maneuvering can be used to get the extra swing.  My players were excited at the revision and started thinking of all sorts of ways to weave in and out of combat to get the Charger Strike bonus on their turn.  It was great.

Defensive Duelist vs using spell slots on reaction spells (shield/hellish rebuke) is a bit of a judgement call, merits to both but for me Hex + damaging cantrips/weapon attacks is always good and worth a spell slot for 1 hour of bonus damage over the reaction spells, but if you want the true capt america look then defensive duelist may not be best, although his twin shields he gets in infinity war could be pretty badass in d&d especially if they can become your spell focus or if your DM is really nice, if they can become a version of a rod of the pact keeper at some point.

If you are thinking of going hexblade/paladin check out nerdarchy on youtube, they do a good video on the combo.

I like that little change to Charger.

As an aside, JC confirmed on sage advice that rogues can dash as an action and/or bonus action...same for monks...https://www.sageadvice.eu/2015/02/10/dash-twice/

So Rogues could get a bit of mileage out of vanilla charger and your own.

out of interest, you say you split it into 2 abilities, did you keep it a feat or change it to a Action everyone can do?

Apologies Hylid, didn't see the question on Defensive Duelist.

DD requires you to be wielding a Finesse weapon and no shield, which means your Shield Fighter combat style isn't really applicable to it.  Shield Master would be a good pick either way, getting your shield's +3 AC bonus to Dex saves and being able to no-sell damage from successful Dex saves is a big deal.  I'd avoid dual-shielding to keep a hand free, especially as you could later fill it with things like special casting foci, or use it to grapple with.

@Rob
I have YuRevised versions of several of the shitty combat feats.  I haven't published them because I'm not sold on the wording yet and I'm not sure how many of them are even viable for it, but they all remain feats.  Charger, Defensive Duelist, Dual Wielder, Savage Attacker, and Weapon Master.  I can discuss them further if you'd like but not in this thread, please.  We've hijacked Hylid's question enough, methinks.

If you are doing hexblade, pact of the blade makes a lot of sense, but I have a different idea.

pact of the chain gives you gift of the ever living one which makes you super easy to heal, and hence quite tanky.  If you don’t mind sacrificing the extra attack, green flame blade or booming blade can make up the difference. 

some would argue about eldritch smite, but this is one spell slot for one shot burst damage when you could alternatively use shadow blade and a Cantrip to do quite a lot of damage and that can be sustained through multiple rounds.

so you trade extra attack and eldritch smite for a really good scout, easy healing, and magic resistance if your dm approves the alternate familiar rules on an imp plus you can do comparable if not more damage.

i only few bad about not having lifedrinker.

id also point out as an alternative that fiend patron let’s you kind of heal when you kill something.

Hexblade is nice to have if the character is starting at a level higher than 1, as they don't get medium armor or a shield as starting equipment. If this sort of thing is important, starting as a fighter and multiclassing at level 2 sounds ideal.

I've seen something run as Capt. America, but it was a fighter build that focused on battlefield control. Start as a human variant for Tavern Brawler or Shield Master and have Athletics proficiency, pick up the other feat later. Start as a fighter for Con saves and starting armor. Take Protection or Defense fighting style, then multiclass into warlock.

Have EB as a 1-handed ranged option, and grab/bash anything dumb enough to approach you. Take Prodigy later and almost never fail shove/grapple checks ever again.

Having a Familiar is an interesting idea.  I had an imp in a 3.5 game and it was pretty useful.  Having a way to have magical Darkvision without needing to take the invocation is not a bad thing.  Having a scout that can fly might also be worth it.  The healing is really good.  I had thought about taking Pally levels later on so that would work nicely with that ability.

https://ddb.ac/characters/11832746/5afZbR

this is a character concept that I use.  warlock pally combo.  it is made to be sort of a tanky melee warlock build.  You can put more into pally if you like but at 5 you get at least extra attack.  (I like having more lock for rp purposes, + I like having more invocations)

I get a few interesting abilities in this build: extra attack, heavy armor and shield, divine smite, spiritual weapon for extra single target damage, spirit guardians for crazy aoe control, ability to self heal with soul cage, cure wounds and dark one's blessing, resistance to damage types, guidance, green flame blade (or booming blade) and polymorph.  There is a lot of utility in this build along with surprisingly good melee prowess.

general idea is mark of making human, pact of chain fiend warlock to lev 15, oath of conquest pally lev 5, orzhov representative profession.

oh yeah, one funny combo is planeshift with the imp.  it is a spell that is touch so the familiar can cast it.  so if there is a really challenging fight ahead that you can scout, then you can sneak the invisible flying imp in there and planeshift something totally out of combat permanently.

That is an interesting build.  I think I would take at least 6 levels of Pally just to get the bonus to saves.  I agree the Green Flame Blade seems to be better for damage than smite.  I had liked the Oath of the Ancients for the magic resistance and plant growth spells.  Plant growth seems like a really good control spell and I think as a Warlock tank my best chance to live is going to be able to control the battlefield.  I do like the Spiritual Weapon spell though.  I think I want more Warlock levels as well.  I have noticed in 5e that you get a lot less spells than you did in 3.5.  I have a lot to think about  for sure.