Following the new Johto-themed update for Pokémon GO, Eevee is now capable of evolving into Espeon or Umbreon. To make the Pokémon evolve into Espeon, rename your Eevee to Sakura. Similarly, give Eevee the name Tamao to make it evolve into Umbreon. A similar technique that was originally discovered last year can be used to evolve Eevee into Vaporeon, Jolteon or Flareon.
Source: The Silph Road
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