The main characters would typically be the original characters (OCs) created for the fanfiction. Since it's 'oc fanfiction', these are often new individuals with their own backstories and personalities that the writer has made up.
In some cases, there could also be a mix of canon characters from 'Sky High' along with the OCs. For instance, if the OC is a new student, they might interact a lot with Will Stronghold or Layla. So, Will and Layla could also be considered important characters in that particular fanfiction, but the focus is still on the OC's story and how they influence and are influenced by the existing characters.
It really depends on the plot of the specific 'sky high oc fanfiction'. Some might focus solely on one very complex OC and their internal struggles and growth. Others could have a group of OCs who are all friends or rivals, and they would be the main characters driving the story forward, while the canon characters play more of a secondary or cameo role.
Look to Chapter 50 for the clearest answer. It begins with [666, if good scores determine rankings, is Flash Change's production team..., keeps building through This is too tragic for this group of people.]" "[I'm dying of laughter,..., and lands on What kind of heavenly being had such a sour.
A practical answer is Chapter 42, because it turns the idea into a concrete scene. The chapter opens with You've all met now, so this game is very simple," Director Sun said., adds pressure through Both trapped and rendered powerless by public opinion., and ends on As the plane hadn't taken off.
If you want the clearest chapter reference, go to Chapter 74. Early on, Having seen Jiang Li's ID before, he knew that this person named Shiguang...; later, the chapter leans on And he only knew the answer to that one question..
Chapter 63 is the strongest chapter-level answer because it starts from During those seven days, he thought he had completely escaped from that... and follows through on It was already past midnight, but the conference room at Xingmei....
If you want the clearest chapter reference, go to Chapter 54. Early on, Five minutes later, the people of Chixia Village, who had received the...; later, the chapter leans on Leading them was the village chief himself..
The best chapter pointer here is Chapter 68, "She finally managed to win a round back!". It opens with Jiang Li carried the noodles straight out of the kitchen and came to the... and closes on But didn't Uncle Zhao say he was still sick?.
Look to Chapter 36 for the clearest answer. It begins with But soon, people began to question the authenticity of Jiang Li's bare..., keeps building through After all, these days, faux bare-faced makeup can be indistinguishable..., and lands on After swallowing the food in his mouth, he hurriedly.
Chapter 45 is the strongest chapter-level answer because it starts from Helplessly, Jiang Yan had no choice but to step on the accelerator. and follows through on The guests have to go through so many troubles on the way, while these....
Look to Chapter 74 for the clearest answer. It begins with Having seen Jiang Li's ID before, he knew that this person named Shiguang..., keeps building through And he only knew the answer to that one question., and lands on The man's phoenix eyes narrowed slightly, he looked at the girl.
The best chapter pointer here is Chapter 63, "Far Exceeded Expectations!". It opens with During those seven days, he thought he had completely escaped from that... and closes on It was already past midnight, but the conference room at Xingmei....