In Pokémon LeafGreen, the Pokémon that you needed to trade in order to evolve them would include Graveler, Haunter, Kadabra and Machoke. However additionally you need to trade Onix, Scyther, Seadra, Poliwhirl and Porygon while they have items attached to them.
you have to trade it to evolve.
you need to trade it then trade it back
he doesn't evolve on his own you have to trade him with one of your friends and then trade him back
Trade, Train, Evolve, Catch, Breed all the pokemon!
Trade it to ruby,sapphire or emerald have them evolve your evee at night then give it back to leafgreen.
You have to trade it to somebody else then get it back
if you give it to seadra then trade it it will evolve into kingdra
You need to trade it to another game to evolve it, it's okay if you trade it back afterwards.
When U trade it by another player and ur age level "LOL"You can't you have to trade it then it will evolve
Machoke evolves once you trade it to someone else.
you trade it while holding an up-grade.
Yes you can trade leafgreen version Pokemon to another leafgreen version.