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

Here is Why You Need An Adapter

The outlet and plug type used in Italy are C, F and L 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

Italy

In Italy, outlets of type C, F and L are in use.

Type C

Type F

Type L