Is an employer hiring an overseas individual under W2 (who physically performs work outside of the US) required to file I-9?

An California LLC (Company #1) is providing staff augmentation to another US entity (Company #2) under a services agreement. Company #2 is requiring that all individuals under the staff augmentation services agreement supplied by LLC #1 to be W2 employees. An individual from outside of the US will be hired under W2 by Company #1. The individual is from Argentina.
1. Can the individual perform work for the Company #1 from outside of the US under W2 without I-9?
2. If, and when, should Company #1 file I-9 for the individual in question?