You Do Need power plug adapter while traveling from Côte d'Ivoire (Ivory Coast) to Cook Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Cook Islands is I and in Côte d'Ivoire (Ivory Coast) are C and E. This is how they look like.

Côte d'Ivoire (Ivory Coast)

In Côte d'Ivoire (Ivory Coast), outlets of type C and E are in use.

Type C

Type E

Cook Islands

In Cook Islands, outlets of type I are in use.

Type I