Since their introduction in Alola, regional variants have been an important part of the Pokémon franchise, and it's likely more will be added when Pokémon Scarlet and Violet are released later this year. For now, very little is known about the Gen 9 games, although the new region will reportedly be based on real-world Spain. Because of this, it's likely new regional variants in Pokémon Scarlet and Violet will likewise be inspired by the country.
So far, the only new Pokémon revealed for Scarlet and Violet are the starters — the Grass-type Sprigatito, the Fire-type Fuecoco, and the Water-type Quaxly. Typically, around 100 new Pokémon get added into a new generation (sometimes more, sometimes far less), which means fans should expect to see many new species debuting when the Gen 9 games come out. However, as with past games since Gen 7, regional variants are to be expected as well.
Related: Pokemon Scarlet & Violet Should Support Hisuian Forms
Pokémon Sun and Moon began this tradition by introducing new types of older Pokémon — like turning the Fire-type Vulpix into an Ice-type — in what would become known as Alolan forms. The Gen 8 games, Sword and Shield, followed by giving new Galarian forms to a number of Pokémon, including trading Fire-type Ponyta and its evolution Rapidash into Psychic-types. A number of regional variants have been added to Pokémon GO and other media since. It's become a popular part of the series, and it's highly likely Pokémon Scarlet and Violet will include regional variants of its own. While none have been officially confirmed yet, there are a number of older Pokémon that would make great candidates for new regional forms.
Eevee evolutions, or Eeveelutions, have been a popular part of Pokémon
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