Slim. You would need to create a web service that uses the Agent Assist API webhook to then call the IBM Watson KMS and respond back to Agent Assist. This should be something that should be implemented on the IBM side but the hosted web service would be possible. Here are some links to get you started. If you get it running, you can productize it and put on AppFoundry.
https://developer.genesys.cloud/blog/2020-02-19-agent-chat-assistant/https://developer.genesys.cloud/blueprints/chat-assistant-blueprint/