In puppies this young its hard to tell- most breeds look fairly simple. Personally I think boxer mix is a fair guess, she does seem to have sort of a short/smushed muzzle, and a face mask is a common marking in boxers- my guess is that's what the shelter was going on. By the other markings/ears maybe she could have pointer in her.
Any guesses at this age are really just shots in the dark, though.
Any guesses at this age are really just shots in the dark, though.