He would probably be angry at first. Naruto is not one to take being trapped lightly. He might shout out in frustration while trying to free himself.
At the start, Naruto would likely be in pain from the bear trap. But being the resilient character he is, he would quickly shift his focus to getting free. He may recall past experiences where he overcame difficult situations. He might also use his Kitsune powers to communicate with any nearby animals for help or at least to get an idea of the area. And all the while, he'd be thinking about getting back to his friends and the village, which would give him the extra motivation to break free from the trap.
Naruto might immediately assess the situation. Since he's Kitsune Naruto, he could have an enhanced sense of his surroundings. He would likely be looking for whoever set the trap or any signs of danger nearby. And he would be determined not to let this trap stop him, so he'd start trying different ways to get out, like using his chakra to weaken the trap.
Perhaps he would be in a situation where he's alone and injured due to the bear trap. This could lead to a moment of self - reflection for Naruto. He might think about his journey, his friends, and how he got into this situation. Then, using his determination and the skills he has learned over time, he would start to analyze the mechanics of the bear trap and look for its weak points. He could also try to sense if there are any nearby threats while he's trapped, as he's always on high alert in dangerous situations.
Sakura might be initially skeptical. She would be worried about Naruto getting involved with a non - human, but after seeing how happy he is, she might come around. Kakashi would probably be more open - minded. He has seen a lot in his life and would likely give Naruto some advice on handling such a unique relationship. Shikamaru would probably find it too troublesome at first, but if Naruto needed his help, he would support him in his own way.
Her friends would likely be very shocked at first. Sakura might be a bit jealous of Naruto's new, more alluring form as a female kitsune. Kakashi, on the other hand, would probably be more concerned about how this transformation affects Naruto's ability to be a ninja. He'd want to make sure she can still fight and protect the village.
Naruto would probably be very surprised. He has heard about Rin from Obito and Kakashi. So when he actually meets her, he might be at a loss for words at first.
He'd probably be shocked by the different power systems. Naruto is used to chakra and jutsus, while Bleach has spiritual energy and zanpakutos. So it would be a big change for him to read about.
Naruto would be excited and ready to face whatever comes. He's always been positive and believing in his ability to change things. So, he'd see it as a challenge to make the future better.
His other friends like Shikamaru would use his intelligence to analyze the situation. He'd try to figure out what kind of jutsu Tsukuyomi is and how it works. Then, he'd come up with a plan. Choji would be there to support everyone physically, ready to fight any threats that might come their way while they're trying to rescue Naruto. And Kiba with Akamaru would use their tracking skills to see if they can find any leads on who trapped Naruto in Tsukuyomi.
Superman might be a bit amused. He'd see the Naruto characters' struggles and compare them to the challenges he faces in Metropolis. Batman would probably study it like he does any case, trying to figure out the motives of the characters in the fanfiction. Wonder Woman would likely be drawn to the strong female characters in Naruto fanfiction, if there are any.
Naruto is often full of surprises. He might first act all nonchalant and say it's just a new thing he's trying. But when he sees Anko's serious face, he would start to panic a bit. He could try to make a joke out of it, like 'Hey, Anko - san, this fanfiction - drink is supposed to make me write better ninja stories!'. In the end, if Anko doesn't buy his story, he would probably just bow his head and admit it was a stupid idea.
He would probably be quite amused by some of his past antics. For example, his constant pranks on Iruka-sensei. But at the same time, he'd also see the pain he carried from not having his parents and realize how that influenced his actions. He might react with a bit of regret for some of the stupid things he did out of loneliness, but also be glad that those experiences made him who he is today.