You Do Need power plug adapter while traveling from French Guiana to Hong Kong.

Here is Why You Need An Adapter

The outlet and plug type used in Hong Kong is G and in French Guiana are C, D and E. This is how they look like.

French Guiana

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

Type C

Type D

Type E

Hong Kong

In Hong Kong, outlets of type G are in use.

Type G