The way Alys' cloak of feathers and claws are described immediately made me think of a design for a piece of clothing in Elden Ring! The Raptor's Black Feathers, while comprised of a half-cape amount of black feathers over a typical black cloak, has the item description "A ritual implement for transforming into a Deathbird, it only by imitation." This connection may be miniscule but knowing GRRM helped write the backstory for the world, maybe Miyazaki and the team at FromSoft did a deep dive of his work beforehand?

This is a lovely, morbid folktale regardless.