How would you define anarchist form?
My initial thought would be that if we take Fassbinder's notion that he wanted his films to "liberate the mind" (which he believed the films of Douglas Sirk did), then Douglas Sirk could be added to your list and even, I would argue, George Cukor and Alfred Hitchcock. Certainly, all three liberated the aesthetic forms of Hollywood cinema (whereas other directors such as Vincente Minnelli or Nicholas Ray could be understood to expand the capacity of the aesthetic forms of Hollywood cinema without liberating it).
Brian