You Do Need power plug adapter while traveling from Hong Kong to Antigua and Barbuda.

Here is Why You Need An Adapter

The outlet and plug type used in Antigua and Barbuda are A and B and in Hong Kong is G. This is how they look like.

Hong Kong

In Hong Kong, outlets of type G are in use.

Type G

Antigua and Barbuda

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

Type A

Type B