To export Thunderbird emails to multiple file formats, use the MacSonik Thunderbird Backup Tool. It can also migrate the Thunderbird emails into multiple email clients like Gmail, Office 365, Yahoo, Zoho, IMAP, Thunderbird, AOL Mail, Hotmail, and iCloud. The tool has a Move Whole Thunderbird Mailbox feature which is used to transfer bulk data or move an entire Mozilla Thunderbird mailbox to a designated saving option simultaneously. Moreover, it ensures complete data security, providing a safe and secure output throughout the process.

For more details: https://www.macsonik.com/thunderbird-backup/