You can easily convert Maildir files using Maildir Converter. The tool supports Mac OS Machines.
Start MacXtra Maildir Converter on your Mac Computer.
Select Maildir file using Add File(s) or Add Folder(s).
Choose saving format from EML, EMLX, MSG, HTML, MHT, CSV, PDF, etc.
You can also Destination path if required.
Mac Maildir conversion for Mac OS process completed successfully, you can see the message of completion.