What are examples of movies where the "sub-story" or "meta-story" mirrors the main narrative?

I’m not positive if this is what you’re looking for, but maybe the (excellent) movie Crash fits the bill.

Intersection with Richard Gere is all I could come up with and it might not be what you are looking for .

A&E’s Pride and Prejudice. Four couples come together. Misunderstanding, miscommunication, pride and, well, prejudices slow the blossoming of the main romance, and in consequently the secondary romance of the main character’s sister.

If I am understanding it correctly…

Oddly enough, another ballet movie (possibly) does this. Center Stage is about a ballet dancer who falls in love with the instructor, while being pursued by a fellow dancer. The story of the ballet they are doing, is about a love triangle that mirrors their story exactly. So when they perform the ballet, it’s quite meta. (the movie isn’t good, by the way.)

Would the movie Adaptation (2002) fit the bill?

Dead Again with Kenneth Branagh and Emma Thompson.

The novel, The Jane Austin Book Club, Karen Joy Fowler, mirrors the six novels that Austin wrote. There is a movie; I have no idea whether it is good or mediocre, or whether it adheres to the original idea of the characters in the novel imitating Austin’s protagonists.

Austin is character and dialog-driven; harder to do in a film. It helps to have read Austin before picking up this novel.

The French Lieutenants Woman and The Great Gatsby both do this, and both are based on novels, of course.

Bowfinger?

The Producers. I think I know the name of the game now.