You Do Need power plug adapter while traveling from American Samoa to New Zealand.

Here is Why You Need An Adapter

The outlet and plug type used in New Zealand is I and in American Samoa are A, B, F and I. This is how they look like.

American Samoa

In American Samoa, outlets of type A, B, F and I are in use.

Type A

Type B

Type F

Type I

New Zealand

In New Zealand, outlets of type I are in use.

Type I