You don't need a fancy e-ink display replacing the plate for that. Something like a green/red led might do (added to the car, besides the plate), if it flashe

You don't need a fancy e-ink display replacing the plate for that. Something like a green/red led might do (added to the car, besides the plate), if it flashes red it means unpaid road tax or "stop me", if it is green it means all good.