Before you can use any paid software to convert OLM to PST format, you should try any easy manual trick. Though the manual trick doesn't convert OLM files into PST format, but you can move email messages and other mailbox data from Outlook for Mac to Windows Outlook. You just need to do these (one by one):
  • Create an IMAP mail account. Gmail is the best option for IMAP.
  • Setup Outlook for Mac with the IMAP mail account.
  • Synchronize Outlook for Mac and IMAP mail account via Gmail label.
  • Now move email messages and other mailbox content from Outlook for Mac to IMAP mailbox folder.
  • Finally move all the mailbox content from IMAP folder to Windows Outlook.

For complete information, you can read this blog post - wordpress.semnaitik.com/2014/02/13/convert-olm-to-pst/

I hope the shared information would be helpful here.

Thanks and best regards.