You Do Need power plug adapter while traveling from South Africa 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 South Africa are C, M and N. This is how they look like.

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N

French Guiana

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

Type C

Type D

Type E