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

Here is Why You Need An Adapter

The outlet and plug type used in Maldives are C, D, G, J, K and L and in Japan are A and B. This is how they look like.

Japan

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

Type A

Type B

Maldives

In Maldives, outlets of type C, D, G, J, K and L are in use.

Type C

Type D

Type G

Type J

Type K

Type L