how can i customize workforce compensation plan approval notification to a different group

Summary:

Our Workforce comp plan use a hierarchy determination formula to find the approver. However, requirement is approval should go to a group of people. Since we cant bring multiple approvers for a single person using formula, we have defined a single person as the approver from the group and asking others of the approval group to act as the proxy approver.

now we need to send the notification of approval to group of people instead of the single approver, We are unable to find how can we restrict this for a plan and what task name we should,

Please help with suggestions.