You Do Need power plug adapter while traveling from Belize to Trinidad & Tobago.

Here is Why You Need An Adapter

The outlet and plug type used in Trinidad & Tobago are A and B and in Belize are A, B and G. This is how they look like.

Belize

In Belize, outlets of type A, B and G are in use.

Type A

Type B

Type G

Trinidad & Tobago

In Trinidad & Tobago, outlets of type A and B are in use.

Type A

Type B