That's literally impossible. The entire point of the game is to have client-side input and for that input to be generated by a human and not a computer. There's no way to move that to a server.
And AFAIK LoL was designed from scratch, it's Dota that actually based on the code of the WoW mod. Not that it matters today, that code is long gone.
Btw, you are thinking of Aeon of Strife (Starcraft mod). World of Warcraft hasn't even been released back then.