Trade Evolution
This system can be a little confusing to work out, so I thought I'd make this guide to see if it could help

I will split this guide up into 4 sections:
- Trade evolution without items
- Trade evolution where items are required
- Preventing Pokémon from evolving via trading
- Additional Notes
1. Trade Evolution Without Items:
This is a simple one. As there is no need for any items for these specific Pokémon, you can just make the trade straight away, and the Pokémon will evolve automatically when the trade is accepted. If they don't, see Section 3. The following spoiler contains the Pokémon that evolve with this method:
(Kadabra) -->
(Alakazam)
(Machoke) -->
(Machamp)
(Graveler) -->
(Golem)
(Haunter) -->
(Gengar)
(Boldore) -->
(Gigalith)
(Gurdurr) -->
(Conkeldurr)
2. Trade Evolution With Items:
This method is a little more complex. First of all, you need to have the relevant item. These can either be bought from the Pokémart (for the price of 10,000 pokemoney each), or by defeating the respective trainers (more details on these below). The receiver of the Pokémon which would be evolving must have the item needed (that means the person who for example, ends up with the Scyther after the trade offer has been accepted.). As with before, the Pokémon will evolve automatically if you have the correct item AND the correct person has the item required. If the Pokémon still doesn't evolve, see section 3. Below is a list of Pokémon that fall into this category:
(Poliwhirl) -->
(King's Rock) (Not yet available) -->
(Politoed)
(Slowpoke) -->
(King's Rock) (Not yet available) -->
(Slowking)
(Onix) -->
(Metal Coat) (Pokémart [10k], Defeat Cynthia [Champions]) -->
(Steelix)
(Rhydon) -->
(Soft Sand) (Pokémart [10k], Defeat Karen [Johto Elite Four]) -->
(Rhyperior)
(Seadra) -->
(Dragon Scale) (Pokémart [10k], Defeat Giovanni [Team Rocket]) -->
(Kingdra)
(Scyther) -->
(Metal Coat) (Pokémart [10k], Defeat Cynthia [Champions]) -->
(Scizor)
(Electabuzz) -->
(Magnet) (Pokémart [10k], Defeat Lance [Champions]) -->
(Electivire)
(Magmar) -->
(Charcoal) (Pokémart [10k], Defeat Galactic Boss Saturn [Team Galctic]) -->
(Magmortar)
(Porygon) -->
(Up-Grade) (Pokémart [10k], Defeat Galactic Boss Cyrus [Team Galctic]) -->
(Porygon2)
(Porygon2) -->
(Up-Grade) (Pokémart [10k], Defeat Galactic Boss Cyrus [Team Galctic]) -->
(Porygon-Z)
(Dusclops) -->
(Cleanse Tag) (Pokémart [10k], Defeat Drake [Hoenn Elite Four]) -->
(Dusknoir)
(Clamperl) -->
(Deepseatooth) (Pokémart [10k], Defeat Dragonmaster [Random Trainers]) -->
(Huntail)
(Clamperl) -->
(Deepseascale) (Pokémart [10k]) -->
(Gorebyss) [Not working currently. Sharks has been made aware.]
3. Preventing Pokémon from evolving whilst trading:
As has been highlighted in the previous two sections, Pokémon will evolve automatically if the right conditions are met. This means you may buy a Shiny Haunter, but receive it as a Shiny Gengar. Not ideal if, for example, Shiny Haunter was the last Pokémon you needed for the Kanto Shinies achievement. So how do you stop that from happening? With the use of this item:

The Everstone, which can be bought from the Pokémart for 10,000 pokemoney. If the receiver has this item, it will prevent the Pokémon in the trade from evolving. If the receiver does not have an Everstone, the Pokémon will evolve automatically. Preventing an evolution in this way does not decrease the number of Everstones you have.
4. Additional Notes
- The only way to get rid of an Everstone (currently) is to go to the Explore tab, then the Sell Items page, and then obviously sell your Everstone(s).
- This is the same for any unwanted evolution items, such as the Dragon Scale or Up-Grade.
- 1 item = 1 evolution. That means, if you receive 5 Scyther's but only have 1 Metal Coat, you will end up with 1 Scizor and 4 Scyther's (the left-most Scyther of the set would be the one that evolved).
This guide is a WIP (Work in progress). Suggestions/feedback are welcome.