Nintendo can't change the pokemon's designs -__- They can't create new regions, mega's, legends, or stories for it.....they only publish it. Sure they make the game's animation, but they don't make ANY of the pokemon in the games. Gamefreak does all of that
I love both of these, but i wouldn't want them to replace the originals. I love the legit Mega Swampert too much, and i think the Mega Sceptile looks badass. I still like these, and i think the would be good alternate mega evolutions.