If you need to export OST file into Outlook pst file format, I would like to refer more effective software. You may use OST to PST Converter which easily recovers corrupted, orphaned & inaccessible OST files and migrates into accessible PST file formate. You can also convert multiple & large size OST file to PST file format. It supports all versions of MS Outlook, like- 2007, 2010, 2013, 2016, 2019, etc.
I have a blog where I defined all the processes of conversion. So, please visit here:-
https://sites.google.com/view/sysbud-software/blog/ost-to-pst-converter