How to Eevee into Espeon
You cannot evolve the Eevee from the Pokemon: Let’s Go, Eevee! data. Thus, you need to catch an Eevee in the wild to evolve it. Once you have caught a wild Eevee, raise your friendship with it. You can do this by camping and playing with it, feeding it at camp, fighting battles with it, and giving it certain items. You can view how friendly your Pokemon is towards you by talking to the kid in the house in Hammerlocke, which is to the right of the first Pokecenter. When you get to pretty friendly with your Eevee, it will evolve at its next level. To get Espeon, you have to evolve Eevee during the day. It should evolve around Level 19.