'I recognise your paper, but you need a revalidation now to align with my currency rules for me to give you my paper'.
That already exists. Unfortunately it is rather to onerous for many.... What people are looking for is simplification of this down to effectively something like an air law exam and skill test.
The requirements to get a permanent certificate are actually the same already at face value.
ATPL JAA to FAA - Pass the ATP exam and check ride on type and bobs your uncle.
ATPL FAA to JAA - Pass the ATPL exam and check ride on type and bobs your uncle.
CPL FAA to JAA - Pass the CPL & IR Exams, training as prescribed and check ride.
CPL JAA to FAA - Pass the Cpl & IR Exams, training as prescribed and check ride.
I only know what the headline 'agenda' items are from discussion with contacts in the EASA licensing team through my interaction with them in the day job. I am sure Pace's contact can supply the full details.
If you just want a plain validation then it is pretty much the same as the 61.75 process but obviously time limited.