So I only just realized the 'variant human' isd pretty much what most other DnD games use, the main bonuses being the extra feat at level 1 and +1 to two attributes in settings where the other races generally get +2 to a single attribute.
This could pretty easily be adapted into Bg3 by at least giving humans a free feat at level 1 which you could use for ability score, and then freeing up the level 4 feat for something else.