I see that this post is a few months old, but I have a work-a-round.
1) Create a master account with manager privileges.
2) Turn on guest uploads & Moderation
The Master Account creates all the Albums and assigns moderated images to those Albums.
Additional users with manager privileges can sort and identify images, but they should not create albums of their own or upload to their accounts. That defeats the purpose. They can see all the albums and move images around to correct sort errors.
Albums created from a selected group of images stay in the original account.
Note: Images cannot be moved between accounts. That is why you want all the albums in the same “master account”
Public? Guests can view all the albums.
Private? Guests can view only specific albums with a link.
I turn off Guest Uploads after a season and open it briefly on request to prevent unwanted uploads.
Example
https://camp-pix.com
(Summer Camp Photos)
Only Camp Horizon albums are public.