In Pokémon Let’s Go Pikachu and Let’s Go Eevee, your partner Pokémon will look a little different depending on whether it’s a male or female. Regular Eevee don’t look any different, regardless of whether they are male or female. But if you get a female Eevee as your partner, you’ll find that its tail seems to be marked by a heart-like pattern. This is only the case for partner Eevee.
The Pokémon Company confirms not all female Eevee have heart patterns in Pokémon Let’s Go Pikachu and Let’s Go Eevee
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