It is actually a very good point that the licenses EASA is apparently requiring would not be legal by State of Registry rules (e.g. FAA 61.3) to fly the same aircraft.
What do you mean "would not be legal"? Part 61 tells you about the requirements and privileges of US pilot certificates. Where does it say you may not also hold an EASA certificate?
Part 91.703 goes on to say (my underline)
(a) Each person operating a civil aircraft of U.S. registry outside of the United States shall—
.......
(2) When within a foreign country, comply with the regulations relating to the flight and maneuver of aircraft there in force"
So on what basis will EASA determine what EASA licenses are required?
Err, on the basis of the EU law already enacted, that Operators of FRA resident in the EU must comply with EASA regs.
brgds
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