You must have defeated the Elite 4 in the game which you are trading from.
By trading with Pokemon Colliseum and XD.
Trading between Crystal and XD is not possible.
by trading it from Pokemon xd
You can only get celebi in Pokemon XD by trading. The only way I know you can get a celebi to Pokemon XD except from events is the Pokemon Colosseum Bonus Disc.
trade them from Pokemon Colesseum/(any other generation lll gamewhere trading is possible)
You can only get Growlithe by trading from Fire Red or Pokémon XD.
Umbreon can only be gained from trading from Ruby, Emerald, Sapphire, Pokemon XD or Pokemon Collosseum.
You can only get one by trading a Growlithe from Fire Red or Pokémon XD.
You can get Lugia, Moltres, Arcticuno, and Zapdos by capturing and then purifying them, and you can get other legendaries by trading with ruby, Sapphire, emerald, firered, or leafgreen after capturing shadow lugia. to trade with those games, connect your gameboy to the gamecube and go to the bottom floor of any Pokemon center in your xd. There should be a trade center there. The rest is just like trading in any other Pokemon game.
no i don't think there is look up on Google Pokemon xd hints ,and cheats
Teddiursa is not obtainable in Leafgreen and the only way to obtain is from trading Teddiursa from either Pokemon Emerald or Pokemon XD Gale of Darkness.
you don't actually. You don't get to have this Pokemon here. The exception is if you get it through trading with other players through a gameboy advance.