Been there and had the problems!!I sold my Portuguese registered car in UK a few years back and ran into major trouble.
I,ll spare you the details but would strongly recommend that you get a proper bill of sale for the transaction and you will also need to get a copy of the new registration document from Holland, proving that the car has left Portugal.
The Portuguese Registry Office and DGV will not remove the vehicle or your name as owner, without these papers.
If the car is not de- registered in Portugal, you will automatically be billed for annual road tax.
So, Bill of Sale, Dutch Reg Certificate (or notorised copy) clearly showing vehicle details, VIN number etc, and your off to the DGV for a long wait !

Please help.

I didn't find the right solution from the Internet.

Exporting a Portuguese registered car - Portugal Forum - 82798 | ExpatFocus.com
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