You Do Need power plug adapter while traveling from Niue to Canary Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Canary Islands are C, E and F and in Niue is I. This is how they look like.

Niue

In Niue, outlets of type I are in use.

Type I

Canary Islands

In Canary Islands, outlets of type C, E and F are in use.

Type C

Type E

Type F