You can add this, and some other info, within the CTI phone widget that your reps are hopefully using. The config is within the SFDC Call Center, this page outlines the available data points:
https://help.mypurecloud.com/articles/customize-interaction-details/
You would first add 'Call.QueueName' then arrow it over into the active column and save your changes.
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Brad Murlin
Zillow, Inc.
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