You could also check out Tumblr. There are a lot of fanfiction enthusiasts on there. Search for relevant tags such as 'Peter Parker 4 years old' or 'Spider - Man 4 years old Peter'. However, Tumblr's search function can be a bit tricky sometimes, so you might need to dig a little deeper.
Some smaller, more niche fanfiction communities dedicated to Spider - Man might also have such fanfictions. You can find these by searching for Spider - Man fan groups on social media platforms and then asking around if they know of any 'Peter Parker shirtless' fanfictions or if they have a collection on their own websites.
You can try websites like Archive of Our Own (AO3). It has a large collection of fanfiction, and you're likely to find many stories related to Hydra and Peter Parker there.
Fanfiction.net might also be a good place. Look for tags related to Peter Parker and then skim through the summaries to find the ones that seem to be quieter. Some authors might label their stories as being more about Peter's internal thoughts or his quieter relationships, like with his aunt May in a more subdued setting.
There are also some specialized Spider - Man or Marvel - related fanfiction communities. These places might be a good bet to find 'peter parker is poisonous fanfiction'. Check out forums where fans discuss and share their own fan - made stories. They may have a link or know where to find this particular piece of fanfiction.
You can find 'Peter Parker and Avengers' fanfiction on websites like Archive of Our Own (AO3). It has a vast collection of fan - created stories in this category. Just search for the relevant tags, and you'll be presented with numerous options.
Some dedicated Spider - Man fan communities may also have a collection of such fanfictions. You can join these communities, introduce your search for Peter Parker sick fanfiction, and ask for recommendations from the members. They might be able to point you to some great reads that you may not find easily through general searches.
Fanfiction.net is a popular site for finding Peter Parker strong fanfiction. It has a wide range of stories, from beginner writers to more experienced ones. AO3 is another good option. It has a more organized tagging system, so you can search for tags like 'Peter Parker' and'strong' to find relevant fanfictions. Additionally, Wattpad may also have some interesting Peter Parker fanfictions, though it's more diverse in terms of content quality.
Some Tumblr blogs dedicated to Spider - Man fanfiction might also have mtf Peter Parker stories. You can search for blogs that focus on unique takes on the character and explore their posts for such fanfictions.
Fanfiction.net is also a good place to look. There are a large number of Spider - Man related fanfictions there. You may need to be a bit more specific in your search by adding keywords like 'omega' and 'Peter Parker' to narrow down the results.
You can start by looking on fanfiction.net. It has a large collection of various fanfictions, including those about a feminine Peter Parker. Just use the search bar and type in relevant keywords.