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

Here is Why You Need An Adapter

The outlet and plug type used in Guyana are A, B, D and G and in South Sudan are C and D. This is how they look like.

South Sudan

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

Type C

Type D

Guyana

In Guyana, outlets of type A, B, D and G are in use.

Type A

Type B

Type D

Type G