You Do Need power plug adapter while traveling from Mozambique to Japan.

Here is Why You Need An Adapter

The outlet and plug type used in Japan are A and B and in Mozambique are C, F and M. This is how they look like.

Mozambique

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

Type C

Type F

Type M

Japan

In Japan, outlets of type A and B are in use.

Type A

Type B