When encountering a person that transforms into a different form, I think we should retain the Anglo-Saxon nomenclature and extend it to describe new combinations of changing from one shape into another.

man changes into wolf -> werewolf (oe. werwulf)

woman changes into wolf -> wifwulf

enby changes into dragon -> mannwyrm

mouse changes to cat -> muscatte

and, of course, kobold changes to a different kobold -> coboldmissenliccobold

That said, I'm stumped at giraffe man... wercamelopardalis?