À priori les 2 sont identiques oui, 1080p et capés les deux à 30 fps parce qu'ils voulaient pas s'emmerder notamment avec la coop qui tourne aussi à 1080p 30fps en splitscreen.
On being asked whether Divinity: Original Sin Enhanced Edition runs at 60 FPS on PS4 and Xbox One, Vincke stated, “No. It’s going to run at 1080p at 30fps. That is because we don’t want to differentiate between split screen and the main mode. You have drop in, drop out multiplayer. People can just jump in with a second controller and start playing in split screen mode that runs at 30 fps.”
source http://gamingbolt.com/divinity-original-sin-enhanced-edition-to-run-at-1080p-and-30fps-dev-explains-lack-of-60-fps