This is not possible by design. Per default, FIDO2 credentials are non-discoverable. This means that the secret is stored on the server, not on the device (but encrypted with a key that is stored on the device). Only discoverable credentials (also called resident keys) are stored on the device and shown by list-credentials. These are typically used for password-less login, e. g. by Google or Microsoft.
This blog post goes into more detail regarding the different credential types: FIDO2, WebAuthn, Passkeys in 2022 and 2023 | Nitrokey