Let file/folder sync work with USB drives and other local folders

I'm a long time WinSCP user and like the Commander style interface (and the "both", "remote", "local" sync behavior) to sync folders. It would be wonderful if there was an option or switch in WinSCP to work with USB thumb drives and backup drives, SMB shares, or even any local folder.

upvoting this suggestion, it would be very useful to have the option to sync between local folders either on the same PC drives, USB-devices or local SMB/CIFS attached NAS drives.

We are working on local-local mode:
https://winscp.net/tracker/1893
Local-local synchronization will be a natural next step.
You can vote for it in the tracker:
https://winscp.net/tracker/1893