I have open source Filezilla FTP server, and if I host files with non-english characters in filenames it converts them into UTF8 format.
Funny to see same folder displayed simultaneously in TC over FTP and native access

I agree it can be tricky to detect that automatically but would like at least manual configuration option for any specific FTP server.
Tested with Fx3 and it works, however requires manual switching to UTF8 encoding for the directory listing.