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

Here is Why You Need An Adapter

The outlet and plug type used in Brazil are C and N 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

Brazil

In Brazil, outlets of type C and N are in use.

Type C

Type N