Divinity original sin is from the same developers as Baldurs Gate and is an absolute banger. Given that the coop Aspekt in dialogues is the absolute same. But the games main focus is IMO the combat which is purely incredible and the build diversity is superb. Also synergies between different players and build is highly encouraged since classes differ greatly in their abilities.
To add to what the other commenter has added. All characters in dialogue are frozen in place and poeple not in dialogue can manipulate them or their surrounding and they can’t react to any of it.