So with the Lore being Separate from the League

Would someone like myself have free reign to write stories based on these characters? What I got from the announcement of "The Great Retcon" is that Riot wants the League to be entirely separate from Runeterra and it's inhabitants. I.E., the League is eSports and entirely Out of Character in it's context, while Runeterra is free to be it's own entity with unique character interactions and story arcs.

Only problem seems, that the entire focus on League of Legends seems to be well, the League portion of that divide. I haven't personally seen any development or effort put forth into releasing new lore for Runeterra and the champions who live there beyond a new video for Amumu "The Sad Mummy".

I could do a weekly episodic story following the adventures of the likes of Vi, Ezreal and others. Completely separate from the League of Legends with no mention of Summoners or the Institute of War as if it never existed. Almost like a fresh start but still heavily based on the old lore interactions of the champions (I.E. Graves and Twisted Fate are rivals, the War between Ionia and Noxus, etc).

Is this a possibility? Or could I get in big trouble for using these characters for stories based in Runeterra?