You Do Need power plug adapter while traveling from American Samoa to Saint Lucia.

Here is Why You Need An Adapter

The outlet and plug type used in Saint Lucia is G 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

Saint Lucia

In Saint Lucia, outlets of type G are in use.

Type G