Well as I said before it's a good thing that we got Volcanion out of the way already. A poster is in line with past movies so the poster is likely movie related but might include new formes/megas too as the February poster during 2012 featured the three Kyurems. The other is likely new game related or a major hint. I don't think it'll be a spin off unless if it's a revival of Stadium, a remake of the Orre games, a sequel to said games.
Edit: Joe says that corocoro never reveals a new main game. I wonder if he meant first to reveal a game (because other events beat it) or what...
Edit II: Serebii and Pokejungle say it's movie related. Which makes sense as the posters are usually movie related. New game could be announced soon after though like on the 27th. B2W2 were revealed on the 26th a day after the Kyurem and Keldeo poster leaked.
The last game they exclusively announced was almost 9 years ago, and pokemon Platinum. After that, everygame was slightly teased for like 5 seconds by the Pokemon company or something else, and Corocoro would be the first to have major info and screenshots on it.
Because of this I'm still calling Pokemon Z next month, based on the theory I posted yesterday, which to me now has some credence.
I also predicted( on smashboards, don't know if I did here), that Corocoro would tease us with a major announcement. This next part I'm pasting over from smashboards as well:
"It was also announced that next month's issue of CoroCoro, due out on February 15th, will have a World Exclusive Scoop Poster and a major announcement that will affect the entire world for the movie."
I called this 100% yesterday that they would tease us with Big news. I also banked on it being Z and still do. While the wording is strange( specifically the part about it affecting the whole world for the movie), I still predict that it will be Z.
It could affect the movie but making volcanion connected to Z somehow. Also their scoops are never word for word( Here's looking at you volcanion is big news for 2016). Actually let's think about that statement a moment...
Volcanion was big news for 2016, his movie is going to have world changing news.
There is definitely something big being planned for him. I don't know what yet, but I think it will tie back to Z. It could go with my theory yesterday that all mythical pokemon could be big factors in Z, hence why they are re releasing them.
Anyway I think we are most definitely getting Z next month based on this, and all the marketing adding up to a February announcement.
The marketing adds up, this scoop adds up, it all makes a lot of sense.
I see Z being announced in A direct before the 15th next month. This is because there is usually a new year direct for Nintendo in January. They will either show Z's logo, or go all out in announcing it with footage and more. Corooro will follow this up
Another thing to consider is that during the Kyreum movie advertisement period, they had an exclusive poster that showcased kyreum's other forums before we knew about them. They could do the same here, but with megas or even new pokemon that we will see in Z, if other theories are correct.