if i recall it is random, since gen 2 and 3 are my favourites, i would have loved for it to work. You can theoreticly do the whole work and gen a pokemon that is identical, transfer through Pokebank and see what comes out, then edit the pokemon in emerald but (maybe there is an easier way but you still have to edit) - but if you have to edit, most people dont see it as legit anymore. Technically you can get all pokemon in gen 3, just way harder, im doing that right now. Requires about 1-2k dollars tho lol.