What's the detailed version of Outlook?
I tested this on my Outlook 365 version 1909. When righting click the sender address and click "add to Outlook contacts", "full
box" appear:

However, when testing on Outlook 2016 MSO (16.0.4849.1000), this dialog appears.

From my test results, this seems to be related with Outlook versions. Please check whether this is the case for you.
I've searched a lot but currently haven't found an official article which explains this difference.
Regards,
Perry
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