Can we send out or receive a completely Custom format xml via Collaboration Messaging (CMK) ?

Summary:

My customer till date has been using a Service Provider(SP) that routes PO messages to the Suppliers registered on it. For the outbound from Fusion, a BIP job runs that gets the POs created/updated/canceled from Fusion Cloud into an FTP folder (in the form of zip) and there is customer's middleware that takes this zip file formats them to the xml that the Service Provider understands which then sends it over to the Vendors. This is not a consistent process and Customer's middleware does run into issues at times making tracking quite difficult.

We even receive ASNs or PO cancelations from Suppliers but via this SP and into OIC. And OIC then uses APIs for the inbound into Cloud.