You Do Need power plug adapter while traveling from Hong Kong to Côte d'Ivoire (Ivory Coast).

Here is Why You Need An Adapter

The outlet and plug type used in Côte d'Ivoire (Ivory Coast) are C and E and in Hong Kong is G. This is how they look like.

Hong Kong

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

Type G

Côte d'Ivoire (Ivory Coast)

In Côte d'Ivoire (Ivory Coast), outlets of type C and E are in use.

Type C

Type E