You Do Need power plug adapter while traveling from Somalia 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 Somalia is G. This is how they look like.

Somalia

In Somalia, outlets of type G are in use.

Type G

French Guiana

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

Type C

Type D

Type E