You Do Need power plug adapter while traveling from Andorra to Cocos (Keeling) Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Cocos (Keeling) Islands is I and in Andorra are C and F. This is how they look like.

Andorra

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

Type C

Type F

Cocos (Keeling) Islands

In Cocos (Keeling) Islands, outlets of type I are in use.

Type I