On August 16th, 2022, Microsoft announced TOTP-based MFA for Azure AD B2C as generally available. The name used for this authentication method is "OATH software tokens", which is another name for TOTP authentication apps like Google Authenticator or Microsoft Authenticator.
This means that, unfortunately, classic OATH tokens that are currently available with Azure AD (still in preview), cannot be used for Azure AD B2C.
Luckily, you can still benefit from Token2 Programmable tokens as they act as a drop-in replacement for TOTP Apps - the only additional step required in this case is transferring the TOTP secret key (shown as a QR code during the MFA enrollment) onto the hardware token using one of our apps (NFC Burner or USB Config tool, depending on the hardware token model you have).
The guide below will provide basic instructions on how to provision a hardware token for Azure AD B2C MFA.