To Split large various PST files into small parts in MS Outlook. I would suggest this
Split Outlook PST Tool. Breaks PST files into small pieces by Date, Size, Year, and Folder. Breaks large PST files in ANSI and UNICODE formats. Breaks oversized PST files without installing MS Outlook. Breaks PST files in all Version of Windows and Outlook. Breaks PST files without damaging any data. Split large PST files with selected dates ranges of sizes. Demo Version also available in this tool. Visit here for more info:
https://www.softakensoftware.com/split-outlook-pst.html