Two options: You can use door apps like Kisi that allow you to enforce 2FA via the phone - you don't necessarily have to use Apple Wallet. If you want to use Apple Wallet you would need an Apple Access certified wall reader, more info and context on the functionality here: https://www.getkisi.com/guides/apple-wallet-access

When you refer to "NFC door" what do you mean with that? You'd need an Apple Access certified NFC reader at the door - here is a guide on the topic: https://www.getkisi.com/guides/apple-wallet-access

You'd need an Apple Access certified reader, such as the Kisi Reader Pro: https://www.getkisi.com/products/reader You can get it with an adapter for Wiegand cable. Generally Apple Wallet for access control info and context can be found here: https://www.getkisi.com/guides/apple-wallet-access

Through our work at getkisi.com, have a bit of experience with this topic: We manufacture NFC card / mobile readers and also allow to enroll 3rd party NFC cards including credit cards: https://docs.kisi.io/references/credentials/physical_credentials/third_party_nfc_credentials?_highlight=nfc When using credit card wallets such as Apple Wallet or crypto related wallets like you suggest, those will encrypt the credit card number and require a security decoding at the receiving end - in this case the NFC wall reader. The only way to use NFC based cards on wallets on Apple devices is via Apple Wallet as outlined here: https://www.getkisi.com/guides/apple-wallet-access