Scott Legal had a TN approval for a Canadian national. The applicant applied with USCIS and was granted a visa for 3 years under the class of graphic designer.
A U.S. citizen who also holds the nationality of a treaty country cannot use that second nationality to receive benefits reserved for E-treaty investors or employees.
In certain situations, such as when you get a new passport or if your answer to the ESTA eligibility questions changes, you will need to apply for a new ESTA.
The U.S. Consulates are currently not conducting visa interviews online and you have to appear for an in person interview (unless you qualify for an interview waiver).
NIW applicants have the benefit of self-petitioning. Entrepreneurs, consultants and other applicants who want more flexibility in their future work plans may prefer to self-petition.