>>19465515Not really.
Lucario's Mega maxes out his aura, but doesn't affect moves that have nothing to do with Aura, like throws and punches.
Charizard's Mega makes his physical attacks (moves that make contact) more powerful, but doesn't affect stuff like Flamethrower and doesn't change the power of his flame breath during one of his throws that have it.
Mewtwo's Mega makes him faster and removes frames from all of his animations, to make him super quick compared to normal.
They're now all different, while still being relatively similar.