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

Swaziland

In Swaziland, outlets of type M are in use.

Type M

Côte d'Ivoire (Ivory Coast)

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

Type C

Type E