Thunderbird to Outlook Converter by eSoftTools is a highly recommended tool for converting Thunderbird files to PST format. It has an amazing feature called "Auto Load," which automatically explores all Thunderbird files on the user's computer. All folder hierarchies, text formatting, meta properties, and HTML formatting are all protected by the tool. It also allows users to combine numerous Thunderbird files into a single PST file. Users can easily export big TB files to the PST file format using this tool.

For more info:- Convert Thunderbird to PST files