Double Arrow button for assigning cases to agents - where is this permission?

In email cases, our supervisors have the double arrow button at the top left that assigns cases to agents.
I want to create a new role for an agent and add that functionality only. Where do I find that?

I might be wrong on this, but If I recall correctly, this isn’t a role within Bright Pattern but an Assignment under the Email Service.
Navigate to the Service that you are using for the email, then “Assignments” tab on the right side window, then adjust the Assignments for Administrators and Reviewers. I know that users under the Administrators could do it, I think Reviewers might also be able to perform the Assign case to agent function as well.

BP helped me set this up successfully: I created a new role (copied the original role and added 3 Supervision privileges:

Define/View subteams of selected agents
View real-time agent metrics
View real-time service metrics

In addition, the agent needed to be added as a supervisor in Users and Teams > Teams > Properties.