You Do Need power plug adapter while traveling from Israel to Monaco.

Here is Why You Need An Adapter

The outlet and plug type used in Monaco are C, E and F and in Israel are C and H. This is how they look like.

Israel

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

Type C

Type H

Monaco

In Monaco, outlets of type C, E and F are in use.

Type C

Type E

Type F