In Photo Center -> Settings -> Organizational Settings -> Site Hierarchy, you can choose which site hierarchy each of your properties (for multi-site clients) would use. This chosen hierarchy should be used for determining which site sections a gallery can be circulated to. Right now, the Default hierarchy is what Photo Center uses for gallery circulation.
Brian McAlister
Per documentation, this was already possible. In an ACS ticket (ACS-24065), I was told "The purpose of Photo Center -> Settings -> Organizational Settings -> Site Hierarchy does configure the site hierarchy and saves back to site service per app in this case photo, but we need to implement it in the Gallery Edit experience." and to submit this on the ideas portal to help the engineering team track the issue.