I would like to recommend here a very effective and secure tool Thunderbird to PST Converter.
· This software is Use the multiple features of the tool and quickly and securely export Thunderbird to PST.
· The software has unique features that allow and user save data into Thunderbird to PST other formats such as EML, EMLX, HTML, MSG.
· There is No file size limitation to convert Thunderbird to Outlook PST.
· Split MBOX file by Size Divides large MBOX files into small PST files in a simple way.
Read more: https://www.kdetools.com/thunderbird/