This Pokémon was not originally found in Alola. Human actions caused a surge in their numbers, and they went feral. They’re prideful and crafty.
– Pokémon Sun Pokédex
Alolan Meowth is Dark type instead of Normal, probably because its Pokedex entries talk about how it has a bad temperament, and is selfish and fickle. It looks more smug than Kanto Meowth.
Instead of evolving by level like Kanto Meowth, Alolan Meowth evolves by friendship.
Stat-wise, it has slightly less Attack than Kanto Meowth, but slightly more Sp Attack. It has the lowest Attack of Dark type Pokemon.