You Do Need power plug adapter while traveling from Liechtenstein to South Africa.

Here is Why You Need An Adapter

The outlet and plug type used in South Africa are C, M and N and in Liechtenstein are C and J. This is how they look like.

Liechtenstein

In Liechtenstein, outlets of type C and J are in use.

Type C

Type J

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N