You Do Need power plug adapter while traveling from Malta to Saint Kitts and Nevis.

Here is Why You Need An Adapter

The outlet and plug type used in Saint Kitts and Nevis are D and G and in Malta is G. This is how they look like.

Malta

In Malta, outlets of type G are in use.

Type G

Saint Kitts and Nevis

In Saint Kitts and Nevis, outlets of type D and G are in use.

Type D

Type G