Hi Brahmeshwar,
If i have understood correctly, you can create a custom agent for the "Role Approval" MSMP workflow (would suggest PFCG based agent if it is same set of team members all the time) and set that as a notification agent to receive a certain custom email template at the end of the Role Owner approval stage.
If you want different groups of people notified based on specific role attributes, then you can create a BRF+ agent and use it as a notification type agent in the MSMP settings.
Hope that helps. I f I have misunderstood anything, please feel free to respond with further information.
Happy new year in advance.