There's two versions of access to "card emulation" mode:
- The EEA-only HCE (which lets you emulate the card in your app in software, for a limited list of use cases, which makes it a non-starter for fully offline systems unfortunately, as there's no protection against exfiltrating any keys from the app), and
- The some-non-EEA-countries-only "full smartcard access" solution, which requires you to pay Apple and do a ton of (presumably also very expensive) certification.
So for different reasons, neither is something in scope for hobbyists at the moment, unfortunately.
- The EEA-only HCE (which lets you emulate the card in your app in software, for a limited list of use cases, which makes it a non-starter for fully offline systems unfortunately, as there's no protection against exfiltrating any keys from the app), and
- The some-non-EEA-countries-only "full smartcard access" solution, which requires you to pay Apple and do a ton of (presumably also very expensive) certification.
So for different reasons, neither is something in scope for hobbyists at the moment, unfortunately.