There's different league clients that allow you to cheat? o_O didn't know this :\
Hello, How can I see enemy summoner names pregame? I know legendary client is capable of doing that, but I didn't find the right version (the newest doesn't let me see enemy summoner names)
By my knowledge there is NO way of knowing who is on the other side, except for premade custom games.
Please hit THANKS if I helped you!
You can always PM me with questions, don't hesitate!
I don't believe this has ever existed, and does not now.