To change your avatar in your chatbot, first upload your image; refer How do I upload an image?
Note - You do not need to connect the Say node, but simply use it to upload the image.
Copy the URL of the image you uploaded.
Go to Bot View Template node in your Bot Manager tab in Experience Designer > Settings
Change the “botAvatarUrl” by substituting it with the URL of the image you uploaded.
To check, open your Bot viewer.
