Simon Levi What exactly do you mean? You can link different cards to different sub-accounts, and also change your choice in the bunq app whenever you want. Whether you pay with the physical card or via Apple Pay makes no difference in this regard.
A feature that only works with the physical cards (and also only when you pay with a PIN) is the Dual PIN feature. For payments with online cards and/or with Apple Pay, it's not applicable.
If you want to easily switch between different accounts when using Apple Pay, you can just use multiple cards and change in the Wallet app. Of course, choose the card before paying, because otherwise it will use your default card. That is more of a usage question for Apple then ;)
See this help entry: https://support.apple.com/en-us/HT201239 And look for the section "Pay with a different card instead of your default card".
