Yep, I agree with you, DensityAltitude. There would be no problem in general.
My specific interest in the OP's point is that one of my types would be very difficult to transfer as there is no longer a sim for the aircraft and, as far as I am aware, no TRE that is EASA approved. Thus it would be possible to use the 500 hour route but the check-ride would be an issue when it came round. Consequently, under the new regs requiring both non-EASA and EASA lic for European OPERATORS in Europe, I might have a problem after the derogation - although the OP's information suggests all would be well as long as I was flying the type on the register of the third-party country for which I had the licence and rating and was in possession of the equivalent EASA licence.
My question, therefore, relates to the Isle of Man situation. If I validate my FAA lic plus type rating and possess the equivalent EASA lic without type-rating, under the Manx system, can I fly in Europe on the Manx reg under the new rules? I have spoken to the Manx authority who were keen to help but were unsure themselves.