It's not okay. 'Stiles' is a character that fans love, and writing about him being abused in fanfiction can have a negative impact on the overall perception of the character. Moreover, it can trigger uncomfortable feelings in the readers, especially those who are sensitive to such topics.
I'm not really into that kind of dark and disturbing fanfiction. However, it's not a very healthy or positive theme. Fanfiction should generally focus on more positive character development and relationships rather than abuse.
He could overcome it through the support of his friends. If his friends are there for him, they can offer a safe space and positive reinforcement. For instance, they can remind him that he is not to blame for the abuse.
Stiles might develop trust issues. Since his own father has been abusive, he may find it difficult to trust other people, especially authority figures. This could impact his relationships in the long run.
The coach may decide to involve other authorities if he becomes more certain about the abuse. He could talk to the school counselor or even the principal. They can then work together to ensure Stiles' safety and get to the bottom of what's really going on.
Most likely not. Fanfiction that involves themes of abuse can be quite disturbing and might not be suitable for younger or more sensitive audiences. It could contain descriptions of difficult situations and strong emotions that some people may find hard to handle.
There are many fanfiction communities out there. Some websites like FanFiction.net might also have 'abused omega stiles' fanfiction. You could also join relevant fan groups on social media platforms and ask for recommendations. They might be able to point you to some great stories that fit this description.
You can try searching on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions, and you might be able to find 'teen wolf stiles abused' fanfiction there by using the search bar and typing in relevant keywords.
One way could be that Stiles finds a support system among his friends. For example, Scott could notice the signs of abuse and encourage Stiles to talk about it. They could then work together to find a solution, like seeking help from an adult they trust, such as a teacher or a local community leader.