Version-exclusive Pokémon in Sun & Moon
Like all the paired games in the Pokémon series, Sun & Moon each include Pokémon that cannot be obtained in the alternate version. To obtain Pokémon missing from your version you need to trade with someone who has the opposite version.
Note: the Lycanroc forms are not listed here as they are not strictly version-exclusive. Both forms are available in the wild in both Sun & Moon; however, Rockruff will only evolve into Midday Form in Pokémon Sun or Midnight Form in Pokémon Moon.