You Do Need power plug adapter while traveling from Belarus to Ethiopia.

Here is Why You Need An Adapter

The outlet and plug type used in Ethiopia are C, F and G and in Belarus are C and F. This is how they look like.

Belarus

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

Type C

Type F

Ethiopia

In Ethiopia, outlets of type C, F and G are in use.

Type C

Type F

Type G