If anything hints about RSE remakes, it will be Jirachi or Deoxys being in them. Mew was in the 8th movie and Celebii was in the 13th movie. If they follow that, one of the event only pokemon for Hoenn will be in the this movie or the next. And it is only December, so it is probably too early to reavel new pokemon at the moment. And with all this Eevee stuff popping up, I think we will see new Eeveelutions, or a new pokemon like Eevee.
Besides the fact, they are really only telling us about the Genesect event coming in Jan. because it is about a month a way.