You Do Need power plug adapter while traveling from New Caledonia to Saint Martin.

Here is Why You Need An Adapter

The outlet and plug type used in Saint Martin are C and E and in New Caledonia are C and F. This is how they look like.

New Caledonia

In New Caledonia, outlets of type C and F are in use.

Type C

Type F

Saint Martin

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

Type C

Type E