In order to use IBM Watson services, you need to configure the Watson Assistant API services.
After configuring it, you can get the Service Credentials to set the credentials in GeneXus. Take a look at Service credentials for Watson services (section Updating service credentials)
Each Conversational Flows instance generates a different skill (formerly workspace). In Watson, you can open the web console and access the skills to edit them.
In particular, you can check the Entity values defined there. The entity values are automatically defined by the Chatbot generator.