All photos are saved to {Internal Storage}/Pictures/PhotoCircle/{CircleName} folder and registered in the system Media Library.

Google Photos does not show all the media from all folders on the main screen. Instead you have to go to “Library” tab then locate your circle in “Photos on device” section above (you might need to tap “View all” to see all folders).

Another way is to use “Files” app and just locate the media files in {Internal Storage}/Pictures/PhotoCircle/{CircleName}.