Spoke too soon. Apparently there are ways to pop up the edit form when you click the "Create Umar" or "Create and Edit...". The idea is to make the name_create method fail. Specifically for res.partner, there is one context that will always fail the name_create, i.e. force_email. If you add {'force_email': 1} into the Customer fields' context, it will pop up the creation form and you can add additional details directly.