>>45744662In my personal autistic experience, there are a few different things that can fit underneath the self insert umbrella despite being quite varied in their uses and average quality
First what most people think of when they hear self insert is when the author writes an idealized version of themselves as a supposedly normal character in the story, examples of this being the original Mary Sue (or what she was a parody of) and that one character on the new power puff girls that is modeled off one of the crew and is a sort of soft love interest for Blossom.
Typically insufferable and riddled with rookie mistakes due to the inexperienced authors that write them, these are often "normal" characters, flaws aside, and often have no (explained) meta knowledge and are often used as "and X was there too"
Second is Isekai, used most prominently in the genre of original fiction of the same name, they are characterised as a person from Earth being sent to another world, often where they can use some degree of meta knowledge or genre savvyness to game the system in some way.
Some consider the genre to be oversaturated, but there's no real inherent issues like the first example.
Third is the hybrid more common in fanfiction, wherein someone from Earth (not always the author) is inserted into a fictional world they are familiar with or at least aware of instead of an "original" work. Often there is no specific justification for the insertion. This I feel has the most potential, specifically in the scenario of taking an established setting, putting it over one's proverbial knee, and shattering the motherfucker.
Other possibilities of course include taking a closer look at parts of the setting/series that were glossed over in the original work and seeing how it would pan out if it were the center of attention, applying "realism" to a situation one would normally forget about and seeing where it goes from there
Obviously it's fucking fiction so there's no real limit
