What benefit does that brings? :-/
If enforces the notion that you should be playing your Paladin according to its tenets. With significant consequences if you act in a way that goes against them.
It indicates that the Tenets of the Paladin are more than just RP Fluff like Cleric Deities are but an actual mechanic for Paladins (Really, Clerics should have a similar mechanic for acting in a way that is not liked by their deity, beyond the few scripted interactions with Shadowheart being punished by Shar)
Didnt find any ...
Lots of unlocking from start, but no "allow respec" not - a - single - one. -_-
https://www.nexusmods.com/baldursgate3/mods/2400That's one I came across immediately just by searching for "Oathbreaker"
I know I've encountered several more when perusing "Paladin" mods looking for subclasses.
On mod.io there's:
https://mod.io/g/baldursgate3/m/seluniteoathbreaker#description Which doesn't outright state it enables respec, but does include the ability to toggle the "Oathbreaker" tag on and off, which should equate to being able to toggle it off and respec (With Oathbreaker being a selectable class so you can respec back into Oathbreaker)