With DMD 2.057, all three overrides fail:

class A{
    void foo(immutable(int)[] x){}
    immutable(int)[] bar(immutable(int)[] x){return x;}
    immutable(int) qux(immutable(int) y){return y;}
}
class B: A{
    override void foo(const(int)[] x){}
    override inout(int)[] bar(inout(int)[] x){return x;}
    override int qux(int y){return y;}
}

The code should compile.