Regulation H was just announced for Pokémon Scarlet and Violet Ranked Battles, and in a shocking twist, it will not expand the pool of Pokémon to choose from.
Since the beginning of Pokémon Scarlet and Violet Ranked Battles, more Pokémon have been gradually added to the meta with each regulation. For example, Regulation B gave us Paradox ‘mons like Flutter Mane and Iron Hands, while Reg G threw in restricted Legendaries like Miraidon and Calyrex. Regulation H, however, does not follow this trend and instead does something very unexpected to shake up the meta.