First you need to beat both xd gale of darkness and leafgreen also you need a GBA to GCN cable. Next in leafgreen find the ruby and sapphire and give it to celio at the one island Pokemon center, the ruby is in mt ember the sapphire is in dotted hole but it gets stolen from you go to five island and inside the rocket warehouse defeat the scientist who stole the sapphire from you. Finally save leafgreen in a Pokemon center with the Pokemon you want to trade, hook up GBA-GCN cable to both the GBA and Gamecube (you can use a Wii as well) then put xd gale of darkness in the gamecube or wii. In xd gale of darkness go to phenac city and go into the Pokemon center go to the basement and talk to the lady she will ask you if you want to trade say yes make sure you have the Pokemon you want to trade in your party. The screen will change and that's when you turn on your GBA wait until the link is established and then using the control stick on the gamecube controller choose the Pokemon you want to trade press the A button on the Pokemon you want to trade then confirm your choice then using the GBA's D pad and A button choose the Pokemon you want to trade. Confirm both your choices wait until the trade is done and it says save completed your able to keep trading when your done say No then turn off the GBA.
Scyther cannot be obtained in leafgreen your going to have to trade one from firered or Pokemon xd gale of darkness to get one.
Since you can't catch chansey you need to trade one from firered, leafgreen or Pokemon xd gale of darkness.
Paras is not in emerald so trade one from firered, leafgreen or xd gale of darkness.
First you need a magmar leafgreen and Pokemon xd gale of darkness can get magmar trade magmar to ruby then breed it hatch the egg to receive magby.
No if you want one you will need to trade a dratini from firered or leafgreen to sapphire then train it to level 55 OR purify the shadow dragonite in Pokemon xd gale of darkness then trade it to sapphire.
trade one in from XD: Gale of Darkness or Pokemon Emerald
You get it at Navel rock. Trade Ho-oh from Pokemon colosseum and trade lugia from Pokemon xd gale of darkness to leafgreen.
You can trade between firered, another leafgreen, ruby, sapphire and emerald also Pokemon colosseum and Pokemon xd gale of darkness.
trade from Pokemon XD: Gale of Darkness (after purification and story mode completed)
Trade one from Pokemon XD: Gale of darkness (after purification and completing story mode).
Have firered or leafgreen trade one to ruby or get the one from Pokemon xd gale of darkness.
You can't get espeon in leafgreen so trade one from Pokemon colosseum or ruby, sapphire or emerald or Pokemon xd gale of darkness.
Navel rock to get there you need a mystic ticket. Also you can trade the lugia from Pokemon xd gale of darkness to leafgreen.
Scyther cannot be obtained in leafgreen your going to have to trade one from firered or Pokemon xd gale of darkness to get one.
Another sapphire, ruby, emerald, firered, leafgreen, Pokemon colosseum and Pokemon xd gale of darkness.
Zapdos is not available in Emerald you will need to trade one from Firered, Leafgreen, or Pokemon XD Gale of Darkness.
You can trade with another sapphire, ruby, emerald, firered, leafgreen, Pokemon colosseum, Pokemon xd gale of darkness and Pokemon box ruby and sapphire.