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

Dubai

In Dubai, 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