You can easily convert Mac MBOX files to MSG using MacUncle MBOX to MSG Converter. The tool supports Mac OS Machines.
Start MacUncle MBOX to MSG Converter on your Mac Computer.
Select MBOX file using Add File(s) or Add Folder(s).
Choose MSG from saving formats.
You can also select the File Naming Option and Destination Path if required.
Mac MBOX to MSG conversion process completed successfully, you can see the message of completion.