you can do it
do this step for migrate intp palpark in rote 221:
first=catch 6 pokemon that you want to migrate from pokemon
ruby/saphirre/emerald/firered/leafgreen.palpark doesn't want to migrate the pokemon fake
version

second=you insert the game boy slot into ds game pak slot

third=whan you turned on the pokemon pearl,
in the menu,you can find words"migrate from saphirre{example}under the new game

then,if you go to palpark,you can in then catch the pokemon you want to migrate
luck hunting

Yes you can transfer pokemon from the GBA to the DS.