There are few easy manual tricks which can help you move or export mailbox data from one PST file into multiple new PST files. Instead of using any paid software, you must try the free manual tricks. If you're trying the manual tricks, there's no need to use any paid software. All you need to use is Microsoft Outlook client. It has few built-in features and functions which you can use here. You can find the complete information in this article - Split PST File into Multiple Parts – Try Few Easy Manual Tricks

Thanks.