You Do Need power plug adapter while traveling from Belgium 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 Belgium are C and E. This is how they look like.

Belgium

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

Type C

Type E

Sint Eustatius

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

Type A

Type B

Type C

Type F