I set Google Photos to automatically back up pictures and videos I take and nothing else. I use an Xperia phone and it comes with a feature to take "Time Shift" photo which is essentially just a series of rapidly taken pictures. It's stored under the "XPERIA" folder inside "DCIM". The problem is it doesn't show up in the setting to exclude folders. And it also gets uploaded to Google Photos, so I'm often flooded with pictures (remember, it's multiple rapidly taken photos) that I don't really need backed up. I can't move the folder either as it is hard coded into the Xperia's system.
I managed this by creating a
.nomedia file in the subfolder. In your case I think this should be
- DCIM - XPERIA - .nomedia
I used ES File Explorer File Manager to create the file but I think you can use the native file explorer if you copy an existing text file and rename it.
.nomedia tells the android media scanner to ignore the folder which stops Google Photo from showing or uploading any files.
A side-effect of this is that most apps will no longer be able to view files in the subfolder.
If you still wanted easy access to the time shift photos you could either install a gallery app that ignores the
.nomedia file or set up a Tasker profile to watch the subfolder and move new files outside of the
DCIM folder (e.g. Pictures folder?).