I’ve tried to remove files and folders. Files just now removed forever.
Still no any .stversions folder in my shared folder.
File versioning is enabled.
Assuming versioning is turned on on deviceB: If you delete a file on deviceA, then you will get an .stversions folder on deviceB. You will not get an .stversions folder on deviceA (regardless of A’s settings) as the OS deletes the file before Syncthing can do anything to remember it or copy it into the .stversions folder. This is expected behaviour.