Here are some example of substitution:
https://imgur.com/a/Qq4bDwU Alligator skin for dragoness
https://i.imgur.com/HON2fOu.png Existing shark skin for dragoness
https://imgur.com/a/Q2Kip3j Mik the Otter skin for cat
https://imgur.com/a/HG6MCc…
Most things could be substituted but hair is the main factor from i see it. It's recommended to look for character who can either change hairstyle and still look like that said character or have no hair at all.