Below are the steps to extract all your email addresses from MBOX files at once.
Using SysTools Mac MBOX Email Address Extractor
The main window of SysTools Mac Email Address Extractor displaying the main screen when the tool gets launched.

Click on "Remove or Remove All" these buttons to remove MBOX files, which you want no more from the selection list

Select your preferable export format among CSV, TXT, PDF, HTML or VCF file format to save extracted MBOX email addresses

Click the Change button to specify where you want your extracted email address files saved on Mac

Click on the Export button to start with the process of extracting email addresses from chosen MBOX files

In this window, you will get summary including source file paths, record count, and it's completion status

Free Download MBOX Email Address Extractor Tool for Mac Download Now