The Bard mod that I had installed during Patch 3 still works without a hitch, surprisingly enough. Although judging from the chatter on the mod page, it sounds like some people trying to install it during patch 4 were having problems. It's been reported that the Paladin mod still works too. I don't know about the status of the rest of the yet to be implemented class mods, but judging from the lack of chatter about them, they either broke or there isn't anywhere near as much interest for those classes for people to check.
Everything else appears to be a crapshoot from what I hear.
EDIT:
https://old.reddit.com/r/BaldursGate3/comments/lu5kzk/list_of_mods_that_still_work_with_patch_4/
