The more i think about it ...
The more i realize that i dont really recall any subclass-specific reaction ...
The only exception is [BERSERKER] tag ... wich gives you saving throw in some dialogues, to control your rage ... advantage to Intimidation almost everywhere (still hate it) ... and really different (and oftem much stupider) dialogues than [BARBARIAN].
OH!
And [DRACONIC BLOODLINE] when you talk to shovel!
But thats all.
Wild magic has some too, according to this outdated dialogue options report :
https://wiki.fireundubh.com/baldursgate3/dialogue-options