You Do Need power plug adapter while traveling from Central African Republic to Costa Rica.

Here is Why You Need An Adapter

The outlet and plug type used in Costa Rica are A and B and in Central African Republic are C and E. This is how they look like.

Central African Republic

In Central African Republic, outlets of type C and E are in use.

Type C

Type E

Costa Rica

In Costa Rica, outlets of type A and B are in use.

Type A

Type B