These are just "backyard mix" breed ducks that hatched in the spring. Just this week I noticed one holding its wings funny. Does this look like the start of Angel wing? Or something else? The wings dont stay close to the body like the other ducks. Hope the pictures help:
From this angle it looks more like when blood feathers[flight] are coming in and they are full of blood and they struggle with holding them up they will build up muscles to eventually hold them at the right angle. If angel wing the wing sticks out like a hitch hikers thumb. Can't see that in your pics.
Here is info on angel wing. https://www.backyardchickens.com/threads/angel-wing-treatment.1252014/#post-20086519