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

Here is Why You Need An Adapter

The outlet and plug type used in Eritrea are C and L 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

Eritrea

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

Type C

Type L