You Do Need power plug adapter while traveling from Christmas Island to French Guiana.

Here is Why You Need An Adapter

The outlet and plug type used in French Guiana are C, D and E and in Christmas Island is I. This is how they look like.

In Christmas Island, outlets of type I are in use.

Type I

In French Guiana, outlets of type C, D and E are in use.

Type C

Type D

Type E

I am from

going to