There is one safe harbor where you will not have to take any action. If you are eligible to take the IRC 911 foreign earned income exclusion (Form 2555) either as a bonafide resident of a foreign country or under the physical presence test, you are specifically exempted from the health
insurance requirements of the Act.
Also, if you are working abroad but covered by the Group plan of your US employer or covered by medicare you are exempt from the Affordable Care Act.
Those who only work temporarily abroad for a few months and then return to the US are not exempted from the Acts requirements and must obtain health insurance or suffer penalties
Nonresidents who are not in the US long enough to become permanent residents (usually 183 days or more) are not required to obtain health coverage.