I feel like I saw a Genesys video somewhere around this recently, but couldn't track it down.
Short answer, you can't auto add images from canned responses or knowledge articles, the agent has to attach the image themselves.
Not sure if the updated messaging UI will support this either:
https://community.genesys.com/discussion/agent-ui-new-messaging-component-beta?ReturnUrl=%2fcommunities%2fcommunity-home1%2fdigestviewer%3fCommunityKey%3dcbd2f140-168a-4c15-aacb-af2b23aa4329
There is however a feature request out there to add this in, which current status is Upcoming Development: https://genesyscloud.ideas.aha.io/ideas/DIG-I-60
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Anton Vroon
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