Getting apple tree cuttings to take root is difficult, but it does work sometime. If you get them to take, just let them grow until they can establish a decent root system and then dig a big rootball and transplant them. If your cuttings don't work out, just get some rootstock and graft next year. Dozier, Dolgo, Hewe's, Transcendent, Callaway and Eliza's Choice are all good crabapples to plant near them for pollination. Plant all of those and you will have a wide drop window, taking you into late fall.