Patience, young Trainer. We will surely get both in time.- the game needs to be exclusive to arcades for a time (licensing agreements, using the arcades as a "beta test", etcetera), so not even Japan have a Wii U release announced yet. When that happens, it will no doubt be announced for a worldwide release too. There is absolutely no chance we will not get this game eventually.
As for Mewtwo... well, we know they're adding characters over time...