Some powers might need to be toned down. For example, Todoroki's ice and fire powers could cause a lot of damage in the real world. He'd have to learn to control them more precisely so as not to cause destruction. And some powers might be more useful in unexpected ways. Uraraka's zero - gravity power could be used for things like helping with construction or moving heavy objects in a safe way.
The characters in the 'bnha big 3 fanfic' are centered around Mirio, Nejire, and Tamaki. However, depending on the plot of the fanfic, it could also involve villains. Imagine a scenario where the big 3 have to face a powerful villain who has a quirk that specifically targets their weaknesses. This would not only showcase the abilities of the big 3 but also introduce new and exciting elements to the fanfic.
Since I haven't read 'the star maker novel', it's difficult to say precisely. However, it's common in science - fiction novels like this to have a protagonist who is either on a quest for knowledge or trying to uncover the secrets of the Star Maker. There might also be a mentor - like figure who guides the main character in their journey. Another possible character could be an alien or some form of otherworldly being that has a connection to the Star Maker or the creation process.
I don't know the exact main characters as I'm not familiar with this specific novel. But they could be the weapon maker themselves, perhaps a young apprentice learning the trade, or an experienced master.
Izuku Midoriya is often a popular choice. His original quirk 'One For All' can be really interesting when combined with gamer - like elements. Writers can explore how he levels it up, discovers new abilities, and overcomes challenges in a more game - inspired way.
Mustard is, of course, one of the main characters. Depending on the fanfic, other characters from the BnHA series like Deku or Bakugo might also be involved. They could be either in a confrontational relationship with Mustard or in a situation where they are trying to understand him better.
Given the title 'ending maker light novel', the main characters might include someone who has the ability to make endings, like a young girl or boy who stumbles upon this power. There could also be an antagonist who tries to disrupt the proper creation of endings, or a mentor - like figure who helps the ending - maker understand and control their power.