If you look at the movie like a live-action anime then the comic relief characters are kind of a must.
Well, it's more like a kaiju film (e.g. the Godzilla and Gamera franchises, or a TV series like Ultraman
or Super Sentai/Power Rangers
), and those are almost always live action. And they usually do feature comic relief characters (although not so much the original Godzilla
, which was a very dark allegory on nuclear weapons and their impact on Japan).
True, giant robots are more known as an anime trope, but there have been plenty in the live-action tokusatsu genre, such as Mechagodzilla, Moguera, and the various Sentai/Ranger Megazords.