But then they tend to feature in the same sorts of tales as selkies and get their skins stolen so they can't change back. And we know there are boy selkies, too.
Not to mention what happens to the boys who are born among the werewolves and don't fit -- the girls escape to be swan, etc. maidens, but the boys?
Fortunately I finally remembered "Marya Morevna" where the three princesses are wooed by an eagle, a raven, and a hawk. No mention is made of specific cloaks, but then, the story is about their brother-in-law; they feature only as help to him.
Now I have only to decide whether bird forms are sex-specific, or whether there are swan men and raven maidens. . . .