disable media folder discovery or exclude custom folders/dirs from detection

I use rclone to mount my nextcloud files directories via webdav to local /mnt/cloud/.
After doing this the nexcloud app media folder discovery detected all my folders as new "upload media folders".

If i try to configure new upload folder via "Settings" -> "Automatic Upload" the App doesnt response anymore because the remote filesystem access is a bit slow and there are a huge amount of "new media folder" that are detected and need to be configured for autoupload. After tap the Settings for Auto upload folder the App hangs and i can choose to close or to wait...

I tried "touch /mnt/cloud/.nomedia" to hide the remote filesystem from android media scan, but this didnt help.

How i can disable the auto media folder detection of Nextcloud App and configure folders manually or how i can exclude a filedir from autodetection?