Maxine's "Oui" shirt is a reference to Oui, a men's adult pornographic magazine published in the United States featuring explicit nude photographs. Oui ceased publication in 2007.
MaXXXine was originally developed as the end of the X trilogy. Ti West later stated in February 2024 that he has plans for a fourth film, which would depend on the third film's reception. In May 2024, West confirmed that he was working on a fourth film and that he may develop it as his next project. In August 2024, in a Reddit Ask-Me-Anything, he said he's happy with where he left it and may have it remain a trilogy.
When Molly Bennett (Lily Collins) talks to Maxine outside of her trailer, she says that actresses have to stick together, similar to what Mitsy (Emma Jenkins-Purro) says to Pearl about sisters in law sticking together in Pearl (2022).
Mia Goth is the granddaughter of Brazilian actress Maria Gladys. As Goth became more popular in Brazil, this became a popular curiosity and ended up going viral after being repeated so many times by people. Marketing for this film in Brazil decided to exploit this and "The granddaughter of Brazilian actress Maria Gladys" succeeded Goth's name whenever it was mentioned while promoting the movie despite Gladys having no connection to it.
After Maxine finishes her audition at the beginning of the film and sees all the other actresses waiting in line, there's a sign that reads "X FACTOR" something mentioned in Pearl (2022) and in X (2022) as the special quality sought for in an actress.