The only way is to trade them from another game or use a cheat device.
You cannot get all 3 Starter Pokemon in Pokemon Emerald without trading for the other 2.
The only two ways to get a torchic in emerald is to choose it as your starter, ortrade with another emerald, ruby, sapphire user that has it.
trade from other games
Mudkip is a starter Pokemon on Pokemon Emerald, Sapphire and Ruby. This means that it is the first Pokemon you get. You get starter Pokemon near the beginning of the game from Professor Birch. Other starter Pokemon are Torchick and Treecko.
The only other way is to cheat.
No you just need to SEE all the Pokemon in emerald pokedex
You can't, but you can by breeding Pokemon or trading. However in Emerald you can by duplication
T-R-A-D-E that spells trade (with someone) You need emerald , ruby/sapphire and a link cable. pick one of the three starters in emerald. then pick a starter that you didn't pick in emerald. then trade the starter over to emerald. then pick the starter that you didn't pick at all and trade it over to emerald. now you have all three starters in emerald! hope i helped!
That person is in firered and leafgreen on two island.
Suicune is not a possible starter Pokemon in emerald you must get a suicune from Pokemon firered or leafgreen.
You can only get Treeko as a starter in Pokemon Emerald.
You pick it as a starter.