Re-using information from the first factor for the second factor

Is it safe to re-use my username and password as information for the 2nd-factor?

For instance:

• the second factor is $H(H(username) \oplus H(password \| SK))$ where $SK$ is the private key.

Would this scheme be secure?

• Please avoid editing your question in such a way that (likely) invalidates existing answers (your latest edit looks like a border-line case for this). – SEJPM Aug 21 '18 at 11:35