You can easily convert Mac DBX files using MacUncle DBX Converter. The tool supports Mac OS Machines.
Start MacUncle DBX Converter on your Mac Computer.
Select DBX files/folder using Add File(s) or Add Folder(s).
Choose the required folder from the selected Outlook Express DBX Folder.
Choose saving format from PST, EML, EMLX, MSG, HTML, MHT, CSV, PDF, etc.
Here we have selected PDF as Saving Option and then choose desired Destination Location & File Naming Option. And Press Export button to start the conversion process.