My partner and I played through Divinity Original Sin 2 many times with co-op, and now we are playing through BG3 and we are having the time of our lives. It's really really good. It's like co-op in DoS2 but I'd say it's even better.
Just make sure you recruit someone and they recruit someone to your party (just like in DoS2) so you both get to control another character. But it's really easy to switch out party members if they are in your camp.