Porco Rosso
An Export Certificate of Airworthiness is NOT required for a US manufactured aircraft, only for foreign manufactured aircraft and THAT export C.ofA. has to come from the country of manufacture NOT country of registry ( unless they are the same of course). A US manufactured aircraft only requires an original FAA cetification either a US C.of A. or a US Export C.of A.
Then a record review to show that no equipment, modifications or repairs have been incorporated that are not FAA approved.
All FAA Ad's must be in compliance and an annual type inspection completed and signed off by FAA IA or repair station.