Hunt around EventViewer on the source of your Powershell events (Applications and Services Logs / Windows PowerShell)
Filter in/out the events you require but as a base you should be looking at
<QueryList>
<Query Id="0" Path="Windows PowerShell">
<Select Path="Windows PowerShell">*</Select>
</Query>
</QueryList>
Usually for a managed install you would add your Xpath to the Log source for the server in the XPath Query box
For an unmanaged install your going to need to get creative and implement this via the WinCollect installer
https://www.ibm.com/community/qradar/2019/03/14/wincollect-7-2-8-stand-alone-cmd-line-with-xpath-option/Good luck and keep us posted.
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JH
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