Her and her brothers powers both come from the mind stone. In age of ultron Maria describes it as neuro-electric interfacing, telekinesis and mental manipulation. Way different than the comics where they simply call her power chaos magic where she'd uses hex's n stuff. I think Tony had called her little witch in age of ultron and she just went with it and added scarlet because of the colour.
Doctor Strange's power doesn't work the same, he had to open his 3rd eye and then study ancient spells for months to begin to do the shyt he now does. I don't think they'll raise Scarlet Witch to that level for simplicity sake.