You Do Need power plug adapter while traveling from Costa Rica to Balearic Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Balearic Islands are C and F and in Costa Rica are A and B. This is how they look like.

Costa Rica

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

Type A

Type B

Balearic Islands

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

Type C

Type F