You can cheat on every site which doesnt force you to download an anticheat client like FaceIT for example.
With the client you cant use LC, without client you can. Matchmaking is UD aswell. Thats it for the current 2.5 public LC version.
As the guy above you just said, you can cheat on Leagues without AC-Client, such as FaceIT. You can play on FaceIT if it doesn't force you to download their shitty Client. If they force you, maybe you had another account or too many reports. Honestly just wait until Jimster releases 3.0 I made the mistake of buying League version while nothing is really supported, but more money for Jimster I guess.