How do I manage multiple Group Admins from a single user

ONE Version - 5.4.13 / Debian 9

I have created 4 different Group-Admins with their respected VDC and resources assigned to them individually, They are configured as expected and each Group-Admin can manage their own Resources and Users.

However I want to create a User that should be able to manage all four Group-Admin from a single User like Group-Manager, so when I login to this Group-Manager I should be able to see all the resources/users assigned/created by these Group-Admin from a single Login.

I dont want to give Group-Manager oneadmin rights as that is not I am looking for. So the Group-Manager should be able to manage and create on behalf of all the Group-Admins. GM should be able to see only resources that are assigned to those 4 Group-Admins.

Group-Manager
|
|__Group-Admin1
|
|__Group-Admin2
|
|__Group-Admin3

I am sure this is possible but not sure how to start with and from where. Any help would be appreciated.

Regards
Kiran