The only way to get a Leafeon is by trading it to a Diamond, Pearl, or Platinum version and raising it up one level near the Moss Rock in Eterna forest.
Chat with our AI personalities
To get both leafeon and glaceon in Pokemon soul silver or heart gold you have to trade it from diamond pearl or platinum.
You have to get it from a friend who has Pearl/Diamond/Platinum
Eevee can't evolve into leafeon in soulsilver you have to trade it to diamond and pearl and evolve it there. The ilex forest doesn't have a Mossy Rock - which is what evolves eevee into leafeon.
I think Leafeon and Iceon are only in diamond pearl and platinum. The only other way to get it is by trade. If you have multiple Ds's, you could transfer to heartgold. This works for Soul Silver too.
sorry you have to trade it to Pokemon soul silver