Say I point to myself and utter,
(1) He is a student.
It was a bit awkward of me to do that but it seems to me that my utterance was true. But what if I point to myself and utter,
(2) She is a student.
It seems that here something much worse has happened. On some treatments of deictic pronouns both (1) and (2) would be undefined, i.e. they get no truth-value. The pronouns have certain "dominating features" and if the purported value doesn't satisfy one of the features it gets rejected as a value and the pronoun goes unassigned. For `he' the features are masculine, 3rd person, and singular -- where 3rd person is understood as being neither the speaker nor the audience of an utterance.
Pointing at yourself in the mirror without realizing that it is you is enough to remove the awkwardness of uttering (1). Is pointing at yourself in the mirror without realizing that it is you and without realizing that you are dressed as a female enough to remove the awkwardness of uttering (2)? Not sure.
Doesn't seem like `I' can refer to someone who fails to satisfy the 1st person feature. But maybe there is a strange case that removes the awkwardness.