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

Here is Why You Need An Adapter

The outlet and plug type used in Liechtenstein are C and J and in Brazil are C and N. This is how they look like.

Brazil

In Brazil, outlets of type C and N are in use.

Type C

Type N

Liechtenstein

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

Type C

Type J