You Do Need power plug adapter while traveling from American Samoa to South Africa.

Here is Why You Need An Adapter

The outlet and plug type used in South Africa are C, M and N 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

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N