The reactions of pro heroes to Deku fanfiction could vary greatly. Pro heroes who are more outgoing and friendly, like Mirio, might actively seek out Deku fanfiction just for fun. He could be the type to laugh out loud at the creative and sometimes wacky ideas in the fanfiction. However, more serious pro heroes, such as Aizawa, might initially be skeptical about the whole concept of fanfiction. But if the fanfiction has some deep insights into Deku's character and his journey, Aizawa might start to respect it more.
Some might feel honored. They see it as a form of recognition of their importance in Deku's story or in the overall My Hero Academia universe. For instance, Iida could see his friendship with Deku being explored in a fanfiction as a compliment to their real - life bond.
Green Lantern would use his power ring to create various constructs. He could create a large, impenetrable cage around Superman to stop him from escaping with Batman. He'd also use his ring to scan Superman for any signs of external influence, like magic or some sort of alien technology that's making him act this way.
One common theme is romance. Many fics explore a romantic relationship between the reader and Hawks. Another theme could be friendship, where the reader becomes a close friend to Hawks and helps him through his struggles.