You Do Need power plug adapter while traveling from American Samoa to Solomon Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Solomon Islands are G and 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

Solomon Islands

In Solomon Islands, outlets of type G and I are in use.

Type G

Type I