And when I bought my house for cash, I signed absolutely nothing. How does either story relate to the president’s constitutional duties?
Since the Constitution is silent on what qualifies as an “official signature”, a Court would likely consider what is deemed an “official signature” generally. Electronic signature is considered official in corporate governance, financial transactions, legal proceedings, and even legislative action.
There is no reason to think it would be ruled unofficial exclusively for the purpose of executive authority ... and thus it would be a Presidential signature for the purpose of Constitutionality.
SnakeDoc