>>26523549My guess as to why it's an equivalent to mega evolution and not specifically mega evolution is that Team Flare will drain all mega evolution energy for their weapon meaning Ash Greninja will be the only Pokémon able to fight against them since it doesn't run on that energy.
>>26523610If it were up to me, when it comes to old mega evolutions I'd just have an NPC in future games give you a Pokémon's mega stone when you go talk to him with said Pokémon in your party, while I'd hide just the new mega stones in the game world instead of all of them.