Pokémon that evolve via trade are Onix, Scyther, Seadra, Poliwhirl, Haunter, Kadabra, Machoke, Boldore, Clamperl, Porygon, Porygon2, Rhydon, Shelmet, Karrablast, Dusclops, Electabuzz, Magmar, Feebas and Gurdurr. Onix and Scyther however need the Metal Coat item to evolve via trade whereas Seadra and Poliwhirl need a King's Rock item in order to evolve via trade.
you just trade it and it evolves during the trade. then ask your friend to trade it back
This means a Pokemon will evolve during a trade some example Pokemon that evolve during trade are: Haunter, Graveler, Machoke. There are plenty more than that so keep trading.
You have to trade kadabra with a friend which it will evolve during the trade then just trade back
Haunter evolves during trade.
It varies from Pokemon to Pokemon levels they evolve on range from: 6-55. Some Pokemon only evolve under certain conditions: Some evolve if exposed to evolutionary stones like a fire stone, Some evolve only if you trade them to a friend, Some Pokemon evolve during trade but only if they hold a certain item like metal coat, Some Pokemon evolve if they have max friendship with there trainer, Some Pokemon evolve during certain times or evolve at certain areas, Some Pokemon will only evolve if there a specific gender.
Kadabra only evolves during a trade.
Kadabra only evolves during a trade.
You have to trade the Pokemon to evolve it.
Seadra will only evolve during a trade while it holds dragon scale.
of course it depends on what Pokemon it is and you have to purify it first
you trade him. and he will evolve into gengar. you trade him. and he will evolve into gengar.
You can't. You can either trade it to a person who will definitely trade it back, or wait for a person to trade a Pokemon that will evolve by trade to you