At the behest of my kids, I’ve written a 150k word reimagining of one of their favorite properties (an Anime/Manga) that incorporates new characters into the world. Sadly, it falls squarely in the “it’s copyrighted material,” so I cannot actually publish it. However, they want to share with their friends and said I should put it online. What are some good sites? Is Archive of Our Own still the best?
If you want to share it with other kids, I’d suggest publishing it on something non-specialised and just sharing a link. You can do AO3 as well for the larger world.