It has been a while since Pokemon XY was released and there is only a handful of Mega Evos, since GF usually has everything stored on the game I can't really consider they will add the other mega evos through DLC, I am pretty sure everything including the needed stones are coded into the games... but then, has the game code and the like been completely dug up? is it safe to assume no other pokemon get mega evolutions? if that's the case that's a real disappointment, only a bunch of starters and other pokemon got to shine.