You Do Need power plug adapter while traveling from Curaçao to Sint Eustatius.

Here is Why You Need An Adapter

The outlet and plug type used in Sint Eustatius are A, B, C and F and in Curaçao are A and B. This is how they look like.

Curaçao

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

Type A

Type B

Sint Eustatius

In Sint Eustatius, outlets of type A, B, C and F are in use.

Type A

Type B

Type C

Type F