it uses the same game engine but the combat is a lot less about resource management and more about character builds, the story is good but nowhere near as spectacular as BG3.
It's still one of my favorite games, I can wholeheartedly recommend it. Just don't expect it to be BG2.5, it's a different game
The action system in D2 is soooo good though. Like if I don't spend every action in bg3 I feel like I wasted a turn. D2 lets you bank a few AP if you aren't able to be effective that turn, or just position and save up for a wombo combo next turn. The pyramids let your party split up to explore too which is great.
Oh, absolutely. It's also closer to the PF2e system of handling actions, and since I personally prefer PF2e over DnD5e, it is, if anything, a plus for me
Unlike BG3 where the combat is based upon a TTRPG, the combat in Divinity is designed around Turn Based video games.
All of the abilities have a cooldown instead of being limited resources. Which is difficult to do with pen and paper, but works perfectly on a computer.
The way you do builds is also a lot more dynamic, there isn't really classes as much as there are different fighting styles with abilities which you can mix and match however you want.
The only thing Divinity lacks compared to BG3 is the cutscenes. Which is kind of important in a story based game.
BG3 is my GOTY. Divinity Original Sin 2 is my favorite game of all time. The story/writing isn't as strong in Divinity but the combat is a work of art. I've beaten BG3 twice, I'm in the middle of a multiplayer run, and I'll run through the game at least once more after the major updates are finished being released. I've finished Divinity six or so times and will continue running the game for a long, long time. It's 110% worth your time and money