Yes you have to trade because you can't get all the Pokemon alone.
Only emerald can get a johto starter however you can trade the johto shadow Pokemon from Pokemon colosseum then breed them in sapphire to get the johto starters you can also trade the johto starters directly from Pokemon xd gale of darkness.
Obtain 200 Pokemon in Pokemon ruby, sapphire or emerald, then go to professor birch and you get to choose one of the johto starters, then you migrate the starter you chose to Pokemon, diamond, pearl, or platinum.
After you beat the Pokemon league in emerald you can get one of the johto starters from prof. Birch then you trade to FR or LG.
There are two main ways you can get the Johto starters in Emerald. You can get one of the three starters from Professor Birch after you have completed the Hoenn dex. But, if you have Pokémon Colosseum, you can catch the Johto starters' evolved forms: Bayleef, Quilava, and Croconaw. If you purify them, you can trade them to your Emerald version if you have the cable that links the GameCube to the Game Boy Advance. Once in your game, you can breed them to get the starters.
All 3 Johto starters cannot be obtained Leafgreen you must trade them from Emerald, Colosseum, or XD Gale of Darkness.
No way you can't get a johto starter Pokemon in Pokemon leafgreen. The only way is to trade with someone to get it.
"You have to have Pokemon colosseum and a gba/cube link cord then you trade the starters to one of the gba games (ruby sapphire emerald leaf green or fire red) then you migrate!"AnswerMigrate the johto starters from emerald to Pokemon diamond or pearl card. Answeryou can also get the johto starters from FireRed by seeing all 150 Kanto Pokemon then go to professer oak he will give you a totodile,cyndaqill or chickorita. Then migrate them to diamond or pearl. remember you have to have at least 6 Pokemon in your PC so be careful.
When you have completed the Hoenn Pokedex in Pokemon Emerald you can pick up one of the Johto Starter Pokemon from Professor Birch. You only get to choose one of them and to get the others you must trade with other players or copies of Emerald that picked the other starters.
The only way to get the other starters if you trade them from a different game to emerald, when you finish the hoenn dex you can choose one johto starter at prof birch's lab.
To get all three Starters in Pokemon Emerald you need to trade for them with Pokemon Ruby, Sapphire or Emerald. This is a mechanic used since the creation of Pokemon to encourage players to get together and trade.
Basically, -just- and I use the term loosely, obtain all Pokemon obtainable in Emerald/ruby/sapphire, on such games, then choose a johto starter (Birch will call you) and trade. Only way, sorry.
No, you need to trade or transfer them from Emerald.