one isn’t supposed to move the camera
Depends on the effect you want. You can do lots of cool/cheesy tricks by moving the camera, like putting the sky from a different place into a different photo, or seeing stars inside a person silhouette. That’s all double exposure, regardless if you like or consider it “proper technique”.
It’s basically DOS3 with different combat, better dialog mechanics and generally better designed. The way exploration, stealth and general flow is essentially the same as Divinity and will play very much the same way, with some improvements on most areas.