Syncing music between device and edrive?

I am wondering. Isn’t /e/ structured in a way that music is snyced between the device and edrive, right? In both directions?
That means:

  • If I put an album on the device from my SD card to the music folder it should be synced to the edrive?
  • And the other way around: It I dump music files into the appropriate folder on edrive it will be synced to my device.
    This should work as long as the toggle under Users & accounts >>> my e-email >>> Account sync >>> Pictures and videos is switched on, right?

For me it seems not to work.
Any advice?

You need the Nextcloud Client. There you can sync files.

Don’t understand: contact for instance can be created in thr ecloud (in the browser) or directly on the device. Subsequently, they are synced.
Why should music files be different?