FAA/JAR,
Being CVD does not bar you from holding a JAA CPL / IR.
The JAA Class 1 Medical will have deviations placed on it restricting you to:
Daytime flight only
NPT (No Public Transport) which means no passenger carriage
But you can do other work, such as instructing, crop spraying (in the UK??) or banner towing.
But you would not be able to fly remunerated passenger transport aircraft.
I am not sure, though, how it would relate to freight work.
Best Regards,
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