Jay would probably be very vocal. He'd be shouting for help and freaking out a bit. Kai would be angry at whoever or whatever hurt Zane and be ready to fight back immediately. Lloyd, being the leader, would try to stay calm on the outside but be very worried inside and start coming up with a plan to help Zane.
The other characters' reactions can vary. Pixal, if she's around, would use her technological knowledge to see if there are any internal damages to Jay, especially if it's related to his electrical components. The villagers of Ninjago might also show their support. They could bring food or offer shelter for Jay to recover. The reaction of the villains would depend on the situation. Some might see it as an opportunity to finish Jay off, while others might be impressed by his courage in getting hurt while fighting them.
One possible scenario in Ninjago Zane hurt fanfiction could be during a battle with a powerful new enemy. Maybe Zane tries to protect his friends and takes a hit that damages his internal systems. His friends then have to find a way to repair him while also fending off the enemy.
His friends, like Kai, would be very protective. Kai might get angry and rush into battle to avenge Lloyd's injury. Jay would probably be more worried and try to use his technical skills to find a solution to heal Lloyd.
One plotline could be that Zane is injured as a result of a malfunction in his own systems. This could be due to a virus or some sort of interference. His friends would then have to figure out how to fix him while also dealing with the threats that his malfunctioning might pose. For example, if his sensors are off, he could accidentally attack his friends. Another common one is Zane getting hurt while protecting someone. He's always the selfless type, so if a civilian or one of his friends is in danger, he'll put himself in harm's way, and that often leads to him getting injured in fanfiction.
Yuki would likely be very concerned. He has a soft spot for Tohru and would probably rush to her side, trying to find a way to help. He might even blame himself if he thinks he could have prevented it. Kyo, on the other hand, would initially be angry, but that's just his way of showing worry. He would be more hands - on in getting her the help she needs.
One emotional moment could be when his friends find him hurt. Their expressions of shock and worry really tug at the heartstrings. For example, Jay might be speechless for a moment, his eyes wide with fear. Another moment could be when Zane himself is in pain but trying to be strong for his friends, like when he forces a smile through his injuries to reassure them.
Beast Boy would definitely be one of the first to react. He and Raven have a special bond in the Teen Titans, so if Raven gets hurt, he would be extremely worried. He might use his shape - shifting abilities to quickly get to her side or try to find help.
Nya would be very worried. She'd probably stay by Jay's side as much as possible, trying to take care of him and find a way to make him better.
Simon might be in a bit of a panic. Since he's her friend and also not as used to the dangerous situations as the other Shadowhunters. He'd try to do whatever he can to help, like getting help from more experienced Shadowhunters or trying to comfort Clary while she's in pain.
One idea could be a story where Zane and Pixal go on a mission together to a new, uncharted land in Ninjago. They face various challenges that test their relationship and their individual skills. Maybe they encounter a new type of technology that Pixal has to figure out while Zane defends them from the local threats.