Okay. I found out something new today about the Apple Pay cards and their prefered language.
Your iPhone has multiple prefered languages. The first two of them are used for your virtual apple pay card.
For example, this are the settings of my iPhone:
English is first, german is second.
This is how it looks in cardpeek (a software to read out data of your EMV card):
As you can see, it is set to "english first, german second" also.
When I change my language back to german (or any other language) it does not change the language of the apple pay card. The apple pay card language is set when you add your card from the bunq wallet to apple pay.
Maybe for physical cards it means that.. you just not have to set your language to your prefered language when you order your card or pay with it.. you have to set it the whole time to your prefered language (until it is on the EMV chip).