Who do we have to inform to allow us to do the test?
Contact issuing Authority i.e Portugal DCA and see what they require.
I think the important thing is that all TK is done in the same State, All flying would be best done in the same State or you will need to transfer "ATO" in the process. He will require a UK FRTOL here but probably not in Portugal. Its largely worthless here now anyway since they changed the exams. ELP seems to be the all important thing!
You could always try using the "Standard" EASA Forms in the AMC; maybe someone actually uses them!
So much for European common standards and methodology!