Messenger Representatives on your Storefront are able to respond to external inquiries via Messenger, but their profiles are not displayed publicly on your storefront.
Messenger Representatives also have access to all Customer Requests and are able to manage them and respond.
Messenger Representatives & Experts: What's the difference?
Your Storefront Experts are available to message buyers in Messenger and are displayed publicly on your storefront. Experts cannot manage or respond to requests. Messenger Representatives can manage and respond to requests, but they are not displayed publicly on your storefront.
Learn how to add user roles and privileges here.