You Do Need power plug adapter while traveling from Namibia 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 Namibia are D and M. This is how they look like.

Namibia

In Namibia, outlets of type D and M are in use.

Type D

Type M

Trinidad & Tobago

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

Type A

Type B