I can confirm that Kate allows to edit files over FTP/SFTP/SMB and many more smoothly, which works over the KIO virtual file system. You can display the (remote

I can confirm that Kate allows to edit files over FTP/SFTP/SMB and many more smoothly, which works over the KIO virtual file system. You can display the (remote) file tree on the side bar and files are uploaded at save (CTRL+S). When the upload takes longer, you even get a progress bar. It just feels very smooth.