Youssef Also the Apple Card has a card number that never changes, what Apple Card does is it gives you an extra virtual card and blocks online payments for the physical card. If you want to achieve the same, just never use the Metal Card for anything online and create an extra virtual card for your online purchases. And about the printed number on the card, even if bunq wouldn't print it on the card you could still get the details just fine with specific apps via NFC or by reading the magnetic stripe.. so no, "no card number" isn't really possible.
