As you can see, I have disabled Sync. But in Joplin main windows this message appears:
Is it normal? Why is that message shown?
First I hope you read the warning before changing the synchronisation path:
Attention: If you change this location, make sure you copy all your content to it before syncing, otherwise all files will be removed! See the FAQ for more details: https://joplinapp.org/faq/
Secondly, you've disabled the sync interval, which means it's no longer downloading new notes automatically. However it still tries to sync (upload) the notes you modify. Currently it's not really possible to disable sync. You can do so more or less by switching for example to OneDrive or Dropbox sync without login in to these services.
I’ve read the warning. I had not understood that the options I checked don’t disable sync at all but only downloading.