Since few days I've been searching for a solution for a problem described in title.
The problem: I have some images in google photos and I want to move them to a specific album using Google Photo Api. I based on https://developers.google.com/photos/library/guides/upload-media.
All what I found was about upload images. Not moves existing ones
Only solution which I see for now is download an image and upload again in specific album what looks no sense.