The workflow editor isn't that powerful. You can't select a bunch of users with certain attributes and apply an action to them. You'll have to create a custom workflow activity. Run as the admin user to retrieve the list of users with a certain role. Base it off the SDk article Retrieve the Roles for a User
You would need to reverse this expression, so to speak. Add a condition expression on the role link, to match on the role name. Then you would remove the condition expression from the system user link. Make the role link a child of the system user link (right now the systemuser is a child of the role link). Change qe.EntityName to "systemuser".
You'll then need to create an e-mail. See SDK articles on sending e-mail and creating workflow activities. Hope this helps.