No. All of those Mega Pokémon have exactly the same "wavy" style to them, except for the new Mewtwo forme, which makes me think they're fake. Seems a bit dubious to me that the entire new batch of revealed Mega Pokémon has the same wavy style to them when the one that is actually confirmed, does not.
I disagree. Lucario and Blazekin I can see what you're saying, but Absol's lines are all sharp and clear, while the curves on Ampharos are much more soft than the abrupt waves on the fighting types. There's a lot of variety in just the ones shown.
I'm an Atheist, and I'm damn proud of it. If that offends you for whatever reason, shoot me a PM and I'll correct your misconception.
I would say "No" despite Serebii who rarely uploads fake leaks posting it because the Absol part is not fully scanned and hidden as if the scanner tried to hide flaws that might reveal its fake.
EDIT: After two new screen shots were uploaded..I am starting to believe them as they revealed a gym leader who can pull potentials Pokemon to help them evolve into Mega Pokemon and a distribution of Torchic carrying a Megastone...