Ok I might be wrong on this theory but here is what I think. Colette and Mirage both have short hair, look vaguely similar and their personalities seem the same. The only thing is that they're attracted to 2 completely different people. Although I do know that Mirage and Mr. Incredible's "relationship" wasn't a thing, u would think she would still like guys like Mr. Incredible. It is kinda weird in general that Colette fell for Linguini because he is completely different than Colette. I'm not saying ur type in anyone can't change in the span of 3 years but Mirage is attracted to Mr. Incredible who is way opposite from Linguini. I could probably go on and on with this but I really can't so I think that : they are similar but prob not the same person. It is a great theory though.