"Are you wearing pajamas?"
'Pizsamát hordasz/viselsz?' is gramatically correct but these 2 verbs are a bit formal so using in a context of wearing pajamas is quite funny. And I think 'hordani' rather refers to a longer time, not at the moment so 'pizsamát hordasz?' is rather should be translated as' Do you usually wear pajamas?' in that case.
better context: 'A munkában mindig öltönyt hordok' ' I always wear a suit in the workplace'
A similarly colloquial question would be 'Pizsama van rajtad?' But it is a bit more difficult to make.