The Pictures screensaver uses the XDG directories. Those are configured in your ~/.config/user-dis.dirs file. Specifically the "XDG_PICTURES_DIR" entry. If you adjust that it'll use a different set of pictures.
The Pictures screensaver uses the XDG directories. Those are configured in your ~/.config/ user-dis. dirs file. Specifically the "XDG_PICTURES_DIR" entry. If you adjust that it'll use a different set of pictures.