So, I could have sworn I had previously seen someone color correct the nighttime scenes in the first Equestria Girls films in order to figure out what Sunset’s pony colors were in the light. But I couldn’t find such an image here, and decided to try my hoof at doing it myself.
 
Using the Mane Six coats as a match to an earlier scene in the film, I began adjusting various color and shading, etc., settings, to get an approximation of what Sunset would look like in the light. This result is not perfect, but is very close; you can directly compare the colors of the Mane Six between the two images yourself, or of course do a better job than me. While not exact, it’s good enough to get a fair idea of what Sunset’s colors as a pony would look like.