If you need to convert your mbox file to an Outlook PST file, try the most popular eSoftTools MBOX Converter program. It can export single as well as bulk mbox files at once, and it supports all editions of Windows OS and MS Outlook 2019, 2016, 2013, 2010, 2007, & 2003. It also comes with a free sample pack that allows users to convert the first 25 items for free from each mbox folder.
For more info-
https://www.esofttools.com/mbox-converter.html