Do you want to convert Maildir files into multiple file formats? I believe theMacSonik Maildir Converter is the most required solution for converting Maildir files into different file formats. This utility can Export emails and folders of Maildir and Maildir++ files to Office 365, Gmail, AOL, Hotmail, Yahoo Mail, and Thunderbird. The Preview feature of this Mac Tool shows you the emails before they are converted. Additionally, it supports all the versions of MacOS.
Read more- https://www.macsonik.com/maildir-converter/