Originally Posted by Nobody_Special
Well it has been said in an interview by Swen that they are going to follow the D&D combat systems.

Originally Posted by Swen
With respect to the combat system, this is based on D&D, so we’re using their combat system.


https://www.pcgamesn.com/baldurs-gate-3/larian-developer-interview

Keep in mind that his answer was in reply to the interviewer asking how many of D:OS2's features that'd get used in BG3. Aside from confirming that it'll be based on 5e, Swen has been reluctant to share details about BG3's system, so we still don't know if it'll be TB, RTWP, both or something completely different.