If you evolve the Alolan version of Meowth, you will get an Alolan Persian.
Also, the Alolan version has a new shiny version as well, which is dark blue instead of the light gray normal Alolan version.
Both Alolan Meowth and Persian share the Dark-typing in Pokémon Sun and Moon.
No, neither Pichu or Pikachu will have an Alolan Form in Pokémon Sun and Moon, just their final stage, Raichu, and it will be Electric-Psychic.
In Pokémon Sun and Moon, Alolan Raichu is an Electric and Psychic-type Pokémon.
There are 802 different species of Pokemon currently up to Pokemon Sun and Moon. This excludes Mega Evolution forms, Alolan forms, and other varieties of Pokemon.
The Alolan Forms in Pokémon Sun and Moon are:Rattata (Dark/Normal);Raticate (Dark/Normal);Raichu (Electric/Psychic);Sandshrew (Ice/Steel);Sandslash (Ice/Steel);Vulpix (Ice);Ninetales (Ice/Fairy);Meowth (Dark);Persian (Dark);Grimer (Poison/Dark);Muk (Poison/Dark);Exeggutor (Grass/Dragon);Marowak (Fire/Ghost);Diglett (Ground/Steel);Dugtrio (Ground/Steel);Geodude (Ground/Electric);Graveler (Ground/Electric);Golem (Ground/Electric).
You have to get the Moon stone.
In Pokémon Sun and Moon, you can catch several Electric-type Pokémon, including Pikachu, which can be found in the wild on Melemele Island. Additionally, you can encounter Magnemite in the Verdant Cavern and Alolan Raichu, which can be obtained by evolving a Pikachu with a Thunder Stone. Other Electric-types like Electrike and Tapu Koko (the island guardian of Melemele Island) are also available in the game.
The Elite 4 consists of Hala, Olivia, Acerola and Kahili. Hala uses Fighting-type Pokémon such as Hariyama, Primeape, Bewear, Poliwrath and Crabombinable, Olivia uses Relicanth, Carbink, Alolan Golem, Probopass and Midnight Form Lycanroc, Acerola will use Pokemon such as Sableye, Drifblim, Dhelmise, Froslass and Palossand and Kahili will use Pokémon such as Skarmory, Crobat, Baile Style Oricorio, Mandibuzz and Toucannon. There is no Champion in Alola however instead of the Champion you will need to battle someone to defend your title and during your first challenge it will be Professor Kukui who will use Midday Form Lycanroc, Alolan Ninetales, Braviary, Magnezone, Snorlax and his last Pokémon in his party will depend on your Starter's selection so if you had selected Rowlet as your Starter then he'll be using Incineroar, if you selected Litten as your Starter then he'll be using Primarina and if you had selected Popplio as your Starter then he'll be using Decidueye.
Onix does not have a pre-evolution form currently as of Pokemon Omega Ruby and Alpha Sapphire and has not been announced for the Pokemon Sun and Moon games.
It evolves certain pokemon to their next form. Nidorino - Nidoking Nidorina - Nidoqueen Clefairy - Clefable Jigglypuff - Wigglytuff
a moon stone can change a Pokemon to a darker form at night and a sun stone can change a Pokemon to light during the day this only works with certain Pokemon like eevee though
There is no Pokemon moon game.