A quick update, I did accidentally lie to you.
The actual title is Soon I will Be Invincible, by Austin Grossman. I got the audibook from my library, and thought the narration was great.
Austin Grossman, btw, is also a well known videogame writer, and pioneered the Audiolog mechanic in System Shock. That game's basically one of the grandfather games for all computer RPGs. He was also the lead writer on the Dishonored games.
So if you end up liking the book, there's a lot of other interesting places to see how Austin Grossman plays with genere conventions like he does in SIWBI.
There is a book called "Soon, I'll be invincible" that is kind of an "IP safe" version of DC's Justice League. You can see the parallels but different enough to be its own thing.
One of the characters is a fairy warrior that was rumored to be left behind when the fae left the world. If I remember the story right, there was a link to something like the Chronicles of Narnia where some kids went to her world and went back and forth. But finally, the gateways closed leaving one of the children behind and she lamented being cut off from her childhood friends and this magical world.
There is a side story where she has become a "J.K. Rawling" type character, making her life dreaming about returning to her friends and writing books about their adventures that no one thinks is real. She's just this kooky old woman that writes fantastical stories that made her rich. Then the Cyborg hero that is the main character and the Fairy gal (who the Cyborg thought was just milking this old woman's fantasy for marketability) goes to visit her and there is a very emotional talk as the cyborg learns it is all real.
IIRC the fairy warrior tells the cyborg that the cyborg could never go there because of her implants. Too much magic in that world and it would cause her implants to break. The Fairy can't go back because of her orders from Titania. She must wait until she is summoned.
I forget if the old woman is allowed to return.
Apparently the author has a twin brother who writes superhero stories.