On the subject of rumors,
Destructiod has a source from Ubisoft that Beyond Good and Evil is indeed to going to be exclusive to NX.
It's going to be a standalone reboot, that is very heavily expanded. Which will be really cool!
The original story of Beyond Good and Evil is just so good, there is so much they can do to expand the world and graphics. Especially considering that no game has really invoked this type of plot before.
It's supposedly going to have a CGI trailer at the NX reveal, and it will come Summer 2018.