Costing shouldn't impact when supplier delivery goods to customer

 Hi Folks,

Please explain how we can achieve following requirement.

1. XYZ company is assembled the goods and make it as finished product. (Costing Method is Average Costing)

Customer "A" ordered  a Product, 

Due to urgency, XYZ agreed to send goods directly to Customer "A", 

but  "XYZ" company will purchse these goods from "ABC" company, 

Company "A" will pay amount to "XYZ", 

Company "XYZ" will pay amount to "ABC"

How we can achieve this process in Oracle ?

Note:- due to this process, no costing impact because there is no impact in our Inventory in this process.