>>18690082I'm thinking Jolteon gets too narrow of a movepool, so probably Espeon. Just be careful during the Morty fight and he should be fine. But its your call. Their HP and defensive stats are the same, so the choice should be to shore up your coverage. You could wait and make it a vaporeon later if totogator doesn't make it.
Pincushion if its Jolteon, Chen for an Espeon, or Corydoras if you decide on Vaporeon.