These fanfictions are popular because they give fans the chance to be creative with the story. Fans can take the existing world of the House of Hades and add their own ideas. The idea of gods and demigods reading about their own story in a way is also very meta and interesting. It attracts readers who want to see how the characters would react to their own story, and how they might change or influence the events in the fan - created scenarios.
One popular fanfiction could be 'Among the Gods in the House of Hades'. It has an interesting take on how the gods interact with the events of the House of Hades story. Another might be 'Demigods' View in the House of Hades Realm' which focuses on the perspective of the demigods as they experience the world within the House of Hades.
Some forums dedicated to Rick Riordan's works might also have fanfiction shared by the community. You can search for ones that focus on 'The House of Hades' and look for the demigod - related stories there.
There could be a fanfiction where demigods from different cabins team up in the House of Hades in a way that wasn't shown before. They might have to solve puzzles and face challenges together, and their different abilities and personalities would create an interesting dynamic.
It would be quite an interesting scenario. The gods might be amused by the creative interpretations of their stories and characters in the fanfiction. Some might be offended if the portrayals don't match their self - perceived grandeur. For example, Zeus might not like being depicted as a bumbling fool in the fanfic.
Well, if the gods in the Percy Jackson universe were to read 'House of Hades' fanfiction, there could be a lot of chaos. Some gods might be amused by the creative interpretations of their characters. For example, Zeus might be both irritated and intrigued to see how mortals imagine his actions and relationships. He could either decide to punish those who wrote unflattering things or just chuckle at the absurdity.
Apollo would probably react with a great deal of vanity. If the fanfiction depicted him as less than the most handsome and talented god, he'd be miffed. He might even try to inspire the fanfiction writers to change their stories. In contrast, Hades might be more indifferent. Since he's used to being feared and misrepresented, he might just shrug off most of what he reads in the fanfiction.
If gods and demigods read fanfiction, they might be amused. Some might find the creative interpretations of their stories and characters quite interesting. They could also get angry if the fanfiction distorts their image in a way they don't like.
It's a really interesting thought. Maybe some of them would. The younger demigods might be curious about how others imagine their lives and adventures. But the gods, they might be too busy with their own affairs or too proud to bother with fanfiction.
You can try some popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions including those for 'House of Hades'. Just search for 'House of Hades' in the search bar on the site.