This is coming from Laura Kate Dale, who leaked Until Dawn: Rush of Blood before its announcement. According to her, instead of being a sequel, Beyond Good and Evil 2 is apparently being made as some sort of reboot of the series and would release in 2018 (That would explain the change in artstyle imo). Also, it seems there will be a new CG trailer, which will be shown during the NX reveal as an exclusive game.
I think this could be true, especially because ever since this game was re-announced it wasn't reffered to as Beyond Good and Evil 2, but as "a new Beyond Good and Evil game" by Ubisoft. They haven't said the planned platforms too, so there's still a chance that it could be NX exclusive.
Anyways, full source here for those that want more details: