Selling Amigurumi (crochet) Patterns of copyrighted characters?

I saw a shop on Etsy and there was a pattern for 3 of the Disney Princesses for sale. Is that Legal? Doesn't Disney have all the rights to that? I saw another shop with a crocheted doll of The Joker. Isn't that illegal as well? I am curious because if it isn't I want to make a shop.