Custom Fields and Logic: S4CRM Lead/Opportunity to Quote

Loved the blog "https://blogs.sap.com/2018/03/07/one-order-extensibility-in-s4hana-for-customer-management/" and have applied that in an S4HANA scenario to add custom fields to the Lead/Opportunity. We have also added equivalent fields in the SD quotation and the one piece missing from the Blog was how we copy control those custom fields from the Lead/Opportunity into the equivalent fields in the SD quote. Is this performed via BADI instead of via a copy control routine?