You Do Need power plug adapter while traveling from Argentina to Lebanon.

Here is Why You Need An Adapter

The outlet and plug type used in Lebanon are C, D and G and in Argentina are C and I. This is how they look like.

Argentina

In Argentina, outlets of type C and I are in use.

Type C

Type I

Lebanon

In Lebanon, outlets of type C, D and G are in use.

Type C

Type D

Type G