FileZilla does not support changing ownership.
The SFTP technically supports it, though with the SFTP version 3 (that FileZilla supports), it's possible using GUID only (numerical value), not using group name. What is not very user-friendly. FileZilla does not make use of this protocol capability anyway. Also, it's worth noting that the most widespread SFTP server, the OpenSSH, suffers the same limitation.
So you may be able to find an SFTP client that allows changing ownership, but most probably using numerical value only.
WinSCP for instance, can change ownership using both numerical value and group name (for SFTP servers supporting version 4 and newer).
See https://winscp.net/eng/docs/ui_properties
WinSCP is Windows application. But you can run it on OSX under Wine.
(I'm the author of WinSCP)
Just for completeness: The FTP protocol does not have a standard way to change the ownership either. But some FTP servers allows changing the ownership using the SITE
command, e.g. SITE CHGRP
. You can enter that command in FileZilla manually using the Server > Enter custom command.
1Well, I have literally just this minute downloaded WinSCP because FileZilla does not do this, and I have to say even within the first 5 minutes of using it what a great program it is. Thank you so much! – Chud37 – 2015-12-16T08:59:51.607