You Do Need power plug adapter while traveling from Abu Dhabi to Nauru.

Here is Why You Need An Adapter

The outlet and plug type used in Nauru is I and in Abu Dhabi is G. This is how they look like.

Abu Dhabi

In Abu Dhabi, outlets of type G are in use.

Type G

Nauru

In Nauru, outlets of type I are in use.

Type I