s it possible for a Changeling to use their “Change Appearance” ability to produce the visage of a mask they’ve seen – but in fact, is their morphed face? Changelings cannot mimic the appearance of equipment or clothing; this is an important limitation on the power. So by default, no, a changeling can’t appear to be wearing a nonexistent mask. But everything’s up to the DM; if it’s an unpainted leather mask, I mightconsider it.
— Keith Baker (@HellcowKeith) November 27, 2019