I would like to recommend commonly used manual method for Thunderbird to Outlook migration using Eudora mailbox. You can use this method on Thunderbird & other MBOX based email clients mailboxes such as Apple Mail, Entourage, Opera, Netscape, Evolution Mail, Postbox, Sparrow Mail etc.
Manual method
1. First install Eudora on your system.
2. Copy MBOX file and change its extension into MBX – both are family format.
3. Go to Outlook >> Choose file tab >> Import & export option >> select “Import internet mail and address” >> Browse file location >> Select destination folder >> click finish button.
With this method, you can easily export the few MBOX data to Outlook but for the large mailbox, I want to suggest MailsDaddy MBOX to PST Converter. This is the best GUI based application that easily migrates large mailbox to Outlook PST format.
For more information visit: https://www.mailsdaddy.com/mbox-to-pst-converter/