To convert Zimbra files to PST files, I recommend you use Zimbra to PST Converter Tool.

Features include:

• In addition to converting TGZ files into numerous file formats, including PST, EML, EMLX, HTML, OLM, NSF, MBOX, etc.
• Using this tool, you can also convert Zimbra files to Office 365 or Exchange Server accounts directly.
• All MS Outlook versions (2019, 2016, 2013, 2010, 2007, 2003, etc.) can be synchronized with this tool.

Read more: https://www.kdetools.com/zimbra/