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

Here is Why You Need An Adapter

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

Réunion

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

Type C

Type E

Aruba

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

Type A

Type B

Type F