@drmaddkap after pondering this, I think that the way it would work is that the number always appears the right way to you, so if you see someone next to a mirror both the person and their reflection appear with numbers the right way. The numbers are added by your brain, so don’t follow light physics. Also your power can’t make an assessment via TV because you can’t perceive the real person (but I imagine it could work if you’re on the TV set, close enough to the person)

@drmaddkap question: is the number reflected?
For an 8 it might not matter (depending on the typography) but how did the 2 usually appear on a mirror?