When entering the EU with goods to declare, is the duty paid in the country of the first point of entry, or in the country of final destination?
good question depeding where the goods are. In the Hand Luggage in the first Country and checkin where you leave with it.
So check for the fee first maybe its cheaper when you pay in the transit country maybe in the arriving.
So you have to divide it. Travel as an Human is just Schengen important.
You say it write thats means only the Passport nothing else.
Normaly you dont have to pay any Custom Fees when you send Good in the EU Country.
Please Note some Island in the English Channel and other are not an EU/ Custom/ Schengen/... Member!
Switzerland is just a schengen member.