This sounds amazing.
It would take an absurd amount of work, as Solcrushed said, but I think it would be an amazing way to implement this. Icons for the people who want their mains to be known or some form of 'tangible' reward; and for those who like the champions for the champions themselves can learn more about them.
I don't think you'd need everyone to be available at once - do it in batches, maybe?
I dunno, I really, really want to see something like this happen. It would be an incredible way for the lore team to flesh out the champs and to get more information on those we love.
...I almost wanna try writing things like this myself??