> Usually that means scanning a QR code with your bank app on your smartphone where you confirm the amount and recipient, but you can use a physical card reader with your debit card for an OTP

This seems to be mobile-centric system that essentially requires a cell phone, and probably one blessed by Google or Apple. The app will probably leak a huge amount of meta data, far more than a credit card (especially a privacy-oriented prepaid one). This kind of "solution" is dead on arrival as far as I am concerned.

Did you miss the whole part where op talks about using your physical card as an alternative?