Yes you can. You must transfer them from the poketransfer lab in route 15 from D/P/Pt/HG/SS.
For squirtle, charmander, and bulbasaur, you must transfer from HG/SS or use pal park from FR/LG then usepoketransfer lab to 5th gen.
For chickorita, cyndaquil, andd totodile, you must transfer from HG/SS or from pal park to poketransfer lab from emerald.
For trecko, torchic, and mudkip you must transfer from HG/SS or from R/S/E by using pal park and then poketransfer.
For turtwig, chimchar, and piplup use D/P/Pt poketransfer or use the current B2/W2 walmart global link event