You Do Need power plug adapter while traveling from Palestine to Vanuatu.

Here is Why You Need An Adapter

The outlet and plug type used in Vanuatu is I and in Palestine are C and H. This is how they look like.

Palestine

In Palestine, outlets of type C and H are in use.

Type C

Type H

Vanuatu

In Vanuatu, outlets of type I are in use.

Type I