Every Model that has got an NPC assigned to it has got an Image like this, the Images wouldn’t exist otherwise.
Edit 1: Even Unused Ones do as long as the condition above is true. Here are a few:
Dubai
Chongqing (He was used in the ET later down the line, but looking at the Clone Rate in Chongqing, it couldn’t hurt adding him to the Main Mission aswell.)
WC