Permanent would make more sense, I read it as "before a match you can choose to spend stardust and candy to unlock another charged attack" like it was an optional unlockable bonus for that match only.I heard it's permanent. I mean, the alternative was having one charged move like we have right now, which would have made battles even dumber.
I wonder how one even counters stuff like Kyogre though. Natural counters like Quagsire only worked because of Water Absorb and Electric immunity. If the damage formula stays the same, then Kyogre and Mewtwo are going to clean house. Not even niche Pokemon like Ludicolo stand a chance.
I guess Alolan Muk is a decent Mewtwo check.
IGN's video shows them using Garchomp, Regigigas and Smeargle, so they might be coming soon