You Do Need power plug adapter while traveling from Åland Islands to Cuba.

Here is Why You Need An Adapter

The outlet and plug type used in Cuba are A, B, C and L and in Åland Islands are C and F. This is how they look like.

Åland Islands

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

Type C

Type F

Cuba

In Cuba, outlets of type A, B, C and L are in use.

Type A

Type B

Type C

Type L