It looks interesting, I just wish we got a new main series one.
One thing I don't get is that this is supposed to take place in Old Japan, so why is Mewtwo there? I mean, it's been established that Mewtwo is a product of science so it couldn't have possibly existed back then...
It's like Mystery Dungeon mixed With Fire Emblem.
Also, as for the Mewtwo thing, my only guess is that Nintendo didn't think that one through or it's as Fivex said.