GM Daniel King has recently published books on the Kalashnikov and Anti-Sicilians. They are based off of his Chessable Courses. GM Pepe Cuenca also has a course on Chessable. I don't know what resource(s) would be better.
I'd also start following GothamChess because it looks like that is going to be one of his go-to variations of the Sicilian going forward. There aren't too many current high level players that I know that play the defense. One player who has games that might be worth examining is Evgeny Sveshnikov.
What are good recourses to learn the Sicilian defense specifically the Kalashnikov and all other sidelines free or paid