You can now trade-specific Pokémon in Pokémon GO to have them evolve. If you do this, you’ll save a considerable amount of candy, and you’ll be able to improve your friendship with the other trainer in the process.
The trading mechanic is pretty simple. All you have to do is trade the Pokémon you want to evolve with another trainer, and the Pokémon costs nothing to evolve. The other trainer cannot trade it back to you because, in Pokémon GO, you can only trade a Pokémon once. You cannot receive it back from the trainer. You want to make sure you understand what you’re trading them and you’re receiving in return.
However, this doesn’t work for every Pokémon. There are only a handful it works. Here is the list of Pokémon you can evolve through trades:
If you have any of these Pokémon in your collection, reach out to another trainer you trust to trade with them, or ask your friends if they want to exchange one of theirs.
This list is not the final. Developers Niantic is likely to increase this list as time goes on, and more Pokémon comes to the game. We can expect more Pokémon already in the game to receive this because a handful of them show up in the larger Pokémon titles, and you need to trade them to evolve them. We don’t know when this is going to happen. We’ll update this list as we learn about the others, and we can expect it to become a new staple in Pokémon GO.