This thread in the Tips & Tricks forum touches on the ability of an elven Fighter (Samurai) to get advantage on all of their attacks in a round using a Bonus Action, and then using Elven Accuracy to make that advantage better if those attacks are Dexterity (finesse weapons) or Charisma (hexblade multiclass) based. I think that Samurai use Elven Accuracy very well since they can so reliably give themselves advantage. A wider list of things/classes that give Dex/Int/Wis/Cha attacks that Elven Accuracy might go well with, if you can find ways to gain advantage on one or more of your attacks.
Finesse Weapons
Ranged Weapons
Monk Martial Arts
Kensei monk's Kensei Weapons
Battlesmith Artificer's Battle Ready
Hexblade
Shillelagh, either cast normally as a Wisdom spell, or if cast as an Intelligence or Charisma-based spell (such as via a Bard's Magical Secrets feature, or as one of a Pact of the Tome Warlock's bonus cantrips)
Attack spells from Intelligence/Wisdom/Charisma casters
The Grappler feat, if you have a way to make a dex/int/wis/cha attack after grappling someone
For example, could a paladin, barbarian, and fighter use eleven accuracy and roll three d20s and take the highest?
Well yeah, as long as you are meeting the requirement of the feat (have advantage) and are not using Str as the attack stat.
This thread in the Tips & Tricks forum touches on the ability of an elven Fighter (Samurai) to get advantage on all of their attacks in a round using a Bonus Action, and then using Elven Accuracy to make that advantage better if those attacks are Dexterity (finesse weapons) or Charisma (hexblade multiclass) based. I think that Samurai use Elven Accuracy very well since they can so reliably give themselves advantage. A wider list of things/classes that give Dex/Int/Wis/Cha attacks that Elven Accuracy might go well with, if you can find ways to gain advantage on one or more of your attacks.
dndbeyond.com forum tags
I'm going to make this way harder than it needs to be.