How did patterns in the Americas and Polynesia reflect their isolation from main transregional trade networks?

Basically for political interests and expansion.

Infact new leaders could be found in the different new cultures in case of problems with America or Europe. Through the conquest and migration, Polynesian culture was introduced in the isles too, beyond the initial territories

The answer is: Suffering a disadvantage when experiencing an external intervention.

Explanation:

Both countries had advanced in their own way, but were very different from each other, and with the rest of Europe and Asia. On the other hand, this isolation affected trade in both countries due to their lack of relationship with others.

Outside the global network. The Americas and Polynesia were not part of the new international exchange. Some of their societies experienced new problems that put them at a disadvantage when experiencing external intervention.

The answer is: Suffering a disadvantage when experiencing an external intervention.