You Do Need power plug adapter while traveling from Equatorial Guinea to South Sudan.

Here is Why You Need An Adapter

The outlet and plug type used in South Sudan are C and D and in Equatorial Guinea are C and E. This is how they look like.

Equatorial Guinea

In Equatorial Guinea, outlets of type C and E are in use.

Type C

Type E

South Sudan

In South Sudan, outlets of type C and D are in use.

Type C

Type D