You Do Need power plug adapter while traveling from Cape Verde to Marshall Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Marshall Islands are A and B and in Cape Verde are C and F. This is how they look like.

Cape Verde

In Cape Verde, outlets of type C and F are in use.

Type C

Type F

Marshall Islands

In Marshall Islands, outlets of type A and B are in use.

Type A

Type B