I doubt she'll ever get an actual one.



Granted, they haven't given anything that equals official word along the line of "Only ponies can get a cutie mark", but given Twilight's read so much about it (I think she said she read everything about it) and what else happened in that ep, she ended up getting a manufactured wooden one.



With all that alone, I don't think you could give someone a cutie mark through magic either since the appearance of an actual one is magically automatic; the ones Twilight made appear on Apple Bloom didn't stick (for 5 seconds) so they don't count. Maybe if she used the Alicorn Amulet, but if it succeed, or failed with any degree of immediate consequences, it could be the nature would either break from its course, or exact a severe punishment on her even if Celestia wasn't involved; think of the level of Fullmetal Alchemist of punishment.