1. The extension MB Include Exclude doesn't work with MB Relationships. The relationship box will display in all user roles.
2. Then you use the field group with the field type user. In this case, the MB Include Exclude will work but the field type user doesn't have the feature bi-directional like the MB Relationship extension. That means you need to manually select the related editor when editing the subscriber and vice versa.
If you want to display a field group when editing a user role only, please use the option Edited user role. Screenshot https://imgur.com/9qBei7t