Its just that your N reg won't be based in Europe any more.
We'll see. What if I sell my aircraft to "Worldwide Aircraft Rentals, Inc." located in Nassau. From there I rent an N-Reg plane from time to time. I have no idea who is the owner of the company (will be surely a rich American taking advantage of another stupid regulation from the EU), and I have no idea where this aircraft flies to and with whom around the world.
I am not the operator, and the operator is outside the EU, so this aircraft doesn't apply to the new European rules, my FAA IR stays valid. No?