What should I do with this eevee?

It's a matter of luck now, nothing much you can do since you already used the easter egg :p

How common are Eevees around you? I run into at least one or two a day, so I have more Eevee candy than I could ever use. Whenever I get a high CP Eevee, I just evolve it; you can never have too many good defending Vaporeons (this is how I've ended up with 8 each of Vaporeons, Jolteons, and Flareons).

The only real reason I can think of to not evolve the Eevee (other than being candy-limited, if Eevees are rare around you) is if Niantic ever releases additional generations, you might want to save it and turn it into one of those new mons. Of course, who knows when, or even if, Niantic will ever do that; as a longtime Ingress player I'm used to being screwed over by them.

No way is this fact.. Because i had a 33% chance but i did the German name and Chinese name for vaporeon and both evolved into vaporeon the ones i didn't name evolved into jolt and flar..

So i was prob. Lucky but if your gonna evolve it.. It obviously can't hurt anything..

Aquana
Mizuki

Are the 2 names you can try!

Umm, you evolve it and hope it becomes a Vaporeon with your desired moveset and then you power it up. And if it doesn't, you just keep it to level gyms or grind it to candy if it makes you mad enough.....

Save it until trading comes out. That's what I'm doing... You can trade it for a cooler pokemon, or make a new account and trade it to that account, then try the easter egg on that account.