I have suggested many times about using scores on topics to get this done, but for now, you need to create a gamification metric based on topics and provide points (gems) for that topic or set of topics and then use that in Insights to "score" agents. Happy to show this to you or setup this in your ORG.
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Robert Wakefield-Carl
TTEC Digital, LLC fka Avtex Solutions, LLC
Contact Center Innovation Architect
https://www.Avtex.comhttps://RobertWC.Blogspot.com------------------------------