New-SSHSession works fine however and using WinSCP confirms the machine is accepting SCP and SFTP connections fine. Git page for it wasnt overly helpful and it was always a "just works" thing ...

FileZilla: Allows file transfer using both FTP and encrypted FTP, such as FTPS (server and client) and SFTP. WinSCP: A free and open-source SFTP file manager for Windows.