Just what it says in the title. I've seen it praised for its versatility and power, but only ever shown off in Sorcerer builds. Who else is it good for?

Advantage on attacks is obviously always good, so super-advantage is even better, for just about any Elf that makes attacks. But here's some standouts:

• It's a pretty essential component of crit-fishing, which makes it excellent on Champion Fighters, Paladins of all stripes, Barbarians (at least, those willing to be sub-optimal and attack with Dex or Cha instead of Str), and Rogues.
• The increased accuracy it brings is very important for characters that put all their eggs in one attack basket, instead of making multiple attacks per round: rogues and spellcasters are the standout there
• More dice being rolled is more opportunities for a Lucky character or a Divination Wizard to bend fate. It's less that such characters need the feat, but more that it helps their cheaty mechanics be even more over the top. 
• Triple-advantage can do a lot to bump up a lower-than-average hit percentage into something more reasonable. Elven Gishes or other MAD builds that find themselves lagging a bit behind their expected to-hit bonus curve might find some rehabilitation through getting to roll three times on advantage. That also makes it really good for Elves that are using Sharpshooter or Great Weapon Master for attacks. 
• Mounted Combatant is an easy way to get advantage every round, as is Reckless Attack on a Barbarian (strength only, whoops), as is being a Battlemaster with Trip attack, or a Grappler... if  you have a way of investing into reliably having advantage every round, super-advantage is obviously even better, even if you aren't particularly optimized as a crit fisher. Being able to be reasonably certain that you'll never miss an attack for the rest of your life can be a good trade off for funky builds that sacrifice some DPR. 

Quote from Darkmoon250 >>

Just what it says in the title. I've seen it praised for its versatility and power, but only ever shown off in Sorcerer builds. Who else is it good for?

 Anyone who uses anything besides Str for their attack rolls. So basically all Spellcasters and any Dex build. 

Elven Accuracy is an excellent choice for any character that attacks with a non-Strength stat and which has an at least semi-reliable means of generating advantage on its attacks.  Typically, it's so highly prized because it offers a point of almost any stat you could need while also granting a very powerful combat ability.  Rogues are an excellent fit; their Cunning Hide means they can regularly take a bowshot at advantage, and throwing three d20 instead of two means a third chance to score that sweet, buttery SneakaCrit and less chance of losing your entire turn's damage to a miss.  A high elf rogue using Green Flame/Booming Blade for their elven cantrip with Elven Accuracy bolted on somewhere can be horrifying.

Sorcerers and wizards tend to attack with their casting stats on cantrips, and EA can empower high-value attack rolls for leveled spells, though relatively few leveled spells actually allow for an attack roll.  One few people think of, however, is an elven artificer.  All artificers have methods of attacking with Intelligence, and artificers also have access to Faerie Fire for a steady source of advantage.  Especially since Tasha's Cauldron looks like it's going to add the Blade cantrips to the artificer spell list.

Another worthy notable is the Samurai fighter, which can gain advantage on all of its attacks for a turn at will, if only three times per rest.  Nevertheless, an Action Surging samurai with Elven Accuracy can fire a lot of arrows, and with the sheer number of d20s being thrown around you're likely to score at least one crit, if not more than one.  If the same character can attain Hex or Hunter's Mark from a feat...well.  That is, as they say, a lot of damage.

Elven Accuracy is not great for classes/characters that don't tend to make high-value attack rolls.  Neither clerics nor druids tend to get much mileage out of attack rolls, and while bards can attack, most of their attacks are also not phenomenal.  An elven bard of the Sword or Valor colleges with EA may work if it also Faerie Fires things, but a more typical casty bard will not.  Barbarians almost never attack with anything but Strength and so cannot benefit from EA.  Monks and Dexy paladins both love the extra die if they can get it, but outside a couple of janky specific subclass features they don't generally have a way of generating the necessary advantage unless a party member regularly gives it to them.  Unless your game uses the overly-generous DMG flanking rule, at least.

The Hexadin Crit Fishing Smiter and the Samurai Sharpshooter are the two builds I've played where I actually took the feat as an essential component of the build, instead of it just looking like an option on paper. I keep wanting to find a way to somehow justify a Charisma- or Dex-based Barbarian to take advantage of their 9/13/17 Brutal Critical enhancement but... it just doesn't seem realistic, while the Hexadin and Samurai Sharpshooter get HUGE utility out of the feat. 

Now, if JC is wrong about improvised Longbow melee attacks,  and if a Kensai or Hexblade or Battlesmith's selection of "Longbow" survives it being used for improvised melee (or, if they're allowed to pick "Improvised Weapon" after taking Tavern Brawler)..... well then, I think a -10 to hit +20 damage Sharpshooter+GWM build would really benefit a lot with an advantage generation method (mounted combatant? Devil's Sight shenanigans?) and Elven Accuracy :D

Even Dex build Clerics benefit because of either 8th level ability, but more so for Strike.

In my experience, rogues gain the most use out of it, but anyone who uses a non-Strength stat to attack will have a great time with this feat (especially Dex-paladins, Hexblades, Battle Smith Artificers, and so on). 

DEX Fighter Samurai with Sharpshooter and Elven Accuracy is one most reliable DPR Kings of the game.

Best part is that any kind of buff you throw at this build becomes a huge force multiplier, like a simple +1 Magic Weapon spell, Bracers of Archery, Bless and anything else.

Being able to shot 4 arrows (Action Surge) at 1d8 +14 with at-will triple advantage having +4 To Hit at level 5 is really powerful.

Quote from Ir0ns0ul >>

DEX Fighter Samurai with Sharpshooter and Elven Accuracy is one most reliable DPR Kings of the game.

Best part is that any kind of buff you throw at this build becomes a huge force multiplier, like a simple +1 Magic Weapon spell, Bracers of Archery, Bless and anything else.

Being able to shot 4 arrows (Action Surge) at 1d8 +14 with at-will triple advantage having +4 To Hit at level 5 is really powerful.

 Eldritch Knight with Flock of Familiars and a longbow, +2 is pretty gross....

Quote from IamSposta >>

 Eldritch Knight with Flock of Familiars and a longbow, +2 is pretty gross....

 I'm having a hard time visualizing what the combo is there... just the Flock taking Help actions, to let the archer have advantage on up to four targets? Seems decent if you can prepare for a fight, but with a one minute casting time, concentration requirements, and the Flock being vulnerable to attacks and the environment... seems like a lesser version of the Samurai Archer's trick. 

Good for Hexblades, since with an invocation to see in magical darkness, and the Darkness spell (can even get a freebie wih Drow), you're guaranteed your advantage.

Also good for anyone with darkvision in low light and the Shadow Blade spell.

Any crit-fishing build.

Anyone who can get advantage a lot.

So it's very useful for many builds. Basically, every class can benefit except perhaps Barbarian (too many of their main features rely on Strength for attacking).