I think you should try
WholeClear MBOX Converter. It is an effective and easy-to-use program that lets you easily export or convert MBOX files to multiple formats, such as PST, EML, EMLX, HTML, PDF, NSF, O365M Gmail, and many more. It works with MBOX files from all the most popular email programs, such as Thunderbird, Apple Mail, Eudora, Entourage, and more. The application makes sure that all the data is safe during the conversion process by keeping the structure of the emails, attachments, metadata, and folder hierarchy. Users can convert a lot of MBOX files at once using the batch conversion feature, which saves time and effort. It works with every version of Windows and the newest versions of Outlook. The intuitive interface makes the conversion easy and smooth, no matter how much you know about technology. You can try out a free demo version before you buy it.