You Do Need power plug adapter while traveling from Aruba to Réunion.

Here is Why You Need An Adapter

The outlet and plug type used in Réunion are C and E and in Aruba are A, B and F. This is how they look like.

Aruba

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

Type A

Type B

Type F

Réunion

In Réunion, outlets of type C and E are in use.

Type C

Type E