Final answer:
An insurer formed under the laws of another country and transacting business in a state is known as a Foreign Insurer.
Step-by-step explanation:
When transacting business in a state, an insurer that is formed under the laws of another country is known as a Foreign Insurer. Domestic insurers are those that are incorporated within the state they are doing business, while international insurers typically refer to insurers that operate across multiple countries but do not point to a specific relationship with the state in question.
Interstate insurers are engaged in business across state lines within the same country but do not pertain to insurers from another country.