Hi @Roger Roger ,
You could add the second time zone following the path in outlook: File -> Options -> Calendar ->Time zones. Then you could add the second time zone and then both time zones will be displayed in the calendar. But according to my test, if you directly change thie first time zone, then your windows OS time and the time of all items in Outlook will changed.
Below screenshot is the test in my Exchange 2016 lab environment, and using the Outlook 2016.
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