Hoopa comes first in the Pokédex (720 to Volcanion's 721), so they'll most probably reveal it first, as not to leave an empty space in the dex. Volcanion always weirded me out, it is similar to Heatran in being a volcano-related big Fire/something type with an ability that makes it immune to one of it's types, but Heatran is available in-game while Volcanion is event-exclusive. What kind of movie can be made about Volcanion? It's Pokédex entries provide it with no backstory, which is another thing it has in common with Heatran. There were 3 Heatran in the anime, one belonging to the villain in the Arceus movie, other in a Pokémon Ranger episode, and the worst offender being the one belonging to a nameless background character registering for the Sinnoh league. I'm just curious, but Volcanion just feels out of place among other event-only Pokémon to me.