How would we evolve eevee into leafeon and glaceon

Im thinking for the name trick, it'll be snowpoint and eterna, the places of the ice and moss rock

for the evolution, no idea, I think it will be random like the first 3

Other than the Name Trick, I would imagine that they will introduce new Evolution Items for it as they have already done the "Day"/"Night", and while "Sunny" weather is available in literally every location on Earth, "Ice" is not so it would be a terrible idea to introduce evolution based soley on In-Game Weather. But I can see them introducing that in the game because it just makes sense for most Eevee's.

How I would see it going would be like this: "Unique Item for Eevee" becomes a drop item. (I don't know a thing about the games, Manga or most of the Anime, so I have no idea if this actually exists already or not) Use this "Eevee Stone" during Sunny Weather, you can evolve to either Leafeon or Flareon. Use it in "Rainy" weather, you can get Vaporeon or Jolteon. Use it in Party-Cloudy Weather to get Sylveon. Use it in Windy weather to get Espeon or in Foggy weather to get Umbreron.

Note this would NOT replace any of the current methods. So if you haven't used the Name Trick, that still works. If you want to walk an Eevee 10km and evolve it during the Day or Night, that still works. If you just want a random Eevee, you can just evolve it like normal and get either a Jolteon, Vaporeon or Flareon.

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