It has actually passed my mind a few times to be honest. It is possible just need to figure out what system to use because I don't think much combat would happen and I know there are systems for non combat Pen and Paper RPG's. I would always be down to play it would be a lot of fun.
So I'm a professional RPG writer. I have been planning to create a book like this, although not necessarily set in the world of ASOUE.
There are a number of systems that could work. Here are some of my favorites:
Cortex+: This game system (split into three different flavors, Drama, Action and Heroic) lets you abstractly represent pretty much anything. Your character's problems and talents help to propel the game forward.
PbtA/*World: A branch of games spawned from Apocalypse World and its more popular derivation, Dungeon World. Player abilities are written as "moves" that blend seamlessly with the game fiction. Character classes are their own fun little books.
GUMSHOE: Designed for mysteries. I'm less familiar with this system than others. I've been told that it doesn't work well for realistic mysteries as much as it does for fantasy and sci-fi.