Add support for MFA (Multifactor authentication).
Could you be more specific ? Authentication codes, Yubikeys, Duo, etc are all used for 2FA which is a subset of MFA.
Ah yes sorry, in Lastpass you can combine Yubikey + fingerprint reader.
I know it’s not exactly what you’re looking for but you can accomplish that functionality with the Duo integration currently; U2F + Duo Push for example. The downside is it of course requires you to have an active internet connection on the device you’re opening your vault on (assuming a sync’d copy would have otherwise allowed offline use).