In December 2017 Ebay seller tamina123 from Koln in Germany was trying to sell these Portuguese plates. There are 2 plates 77 NH GH but he only puts one photo.
All of these plates are completely wrong. Most of them are German registrations, several from Koln actually, made in Portugal. 77 NH GH is probably a Dutch (Netherlands) registration rather than a Portuguese or German one.
They are just not genuine plates and really are just scrap. Best to not buy any of these.