The FAA has issued a final rule that will require most larger aircraft built after Jan. 1, 2028, to meet new efficiency standards designed to reduce their carbon emissions per passenger mile. The new rule will cover all subsonic jets with a maximum takeoff weight of more than 12,500 pounds and turboprops with an MTOW of 19,000 pounds.
I think we do but not in international waters. Many shipping ships have two engines. The dirty one it uses most of the time and the clean one it uses when getting to or leaving a port.