Ichigo's Hollow powers, if he were to lose control of them in the Avatar world, could be a real threat. However, Korra's connection to the spiritual side of her world (as the Avatar has a connection to the spirit world) might be able to help him regain control. In return, Ichigo's experience in dealing with his inner Hollow could give Korra new insights into facing her own inner demons. Their powers could also interact on a more subtle level. For instance, Ichigo's ability to sense spiritual presences could help Korra detect hidden enemies or threats in the spirit world that are related to her world's problems, and Korra's bending could be used to create barriers or platforms to help Ichigo in battle in a more physical sense.
Ichigo's Soul Reaper powers are based on spiritual energy, and Korra's bending is based on her connection to the elements. Their powers could interact in a way that creates a new form of energy. For example, when Ichigo uses his Getsuga Tenshou near Korra while she's bending, it might create a shockwave that combines the force of the spiritual energy blast with the element she's bending. This could be a very powerful and unique combination that they could use to defeat enemies.
Korra's ability to enter the Avatar state, which gives her enhanced power over all the elements, could be affected by Ichigo's presence. Maybe his spiritual pressure could either stabilize or disrupt her Avatar state. If his spiritual pressure is in harmony with her, it could make her Avatar state even more powerful, allowing her to access new levels of bending. On the other hand, if they are not in sync, it could cause her to lose control. Ichigo's Bankai, with its extreme power output, could also have an impact on the natural elements in Korra's world. It might distort or enhance the flow of the elements, depending on how they interact.
A crossover might involve Hollow Ichigo being drawn to the Avatar state. He could sense the immense power within Korra when she enters the Avatar state and be both intrigued and threatened by it. This could lead to a series of battles and power struggles. Or perhaps some of the villains in Legend of Korra might try to team up with Hollow Ichigo, thinking his power could help them achieve their goals, but in reality, he has his own agenda and would double - cross them at the first opportunity.
Korra would likely be very cautious at first. She's used to dealing with powerful opponents, but Hollow Ichigo's otherworldly nature would be something new. She might try to communicate with him, but if he showed aggression, she'd be ready to fight. Asami would probably be more strategic, trying to figure out his weaknesses. Mako and Bolin would be a bit more intimidated. Mako might use his lightning - bending as a first line of defense, while Bolin would be thinking of ways to use his earth - bending to either trap or slow down Hollow Ichigo.
One idea could be that Ichigo, through some sort of interdimensional rift, ends up in the Avatar world of Legend of Korra. He could initially be seen as a threat due to his otherworldly powers. But as the story progresses, he teams up with Korra to fight a common enemy that is trying to take over both their worlds. His Soul Reaper powers could be used in unique ways, like using his Getsuga Tenshou to blast away dark spirits that are plaguing the Avatar world.
In a fanfiction, characters like Asami from Legend of Korra and Sasuke from Naruto could also interact. Asami might be intrigued by Sasuke's cool and brooding demeanor. Sasuke, in turn, could respect Asami's intelligence and engineering skills. Their interactions could add another layer of complexity to the story, as they come from very different backgrounds yet find common ground in their loyalty to their respective friends and the greater good.
His new powers might make some of his friends a bit wary at first. They could be worried that he's changing too much. But as they see him use his powers for good, they'll likely become more accepting. His enemies, on the other hand, will be more afraid of him and might target him even more.
The 'lemon' aspect might be a bit hard to come by in a clean way as it often involves inappropriate content. But for normal Korra and Mako fanfictions, you could also try FanFiction.net. Some stories there might show their relationship developing, their adventures together, and how they support each other, which can be really interesting to read.
Yes, there are likely some popular ones. Often, these fanfictions gain popularity because they explore the relationship between Mako and Korra in a way that the original show might not have fully delved into. For example, some might focus on the emotional build - up to the kiss, which can be really engaging for fans who are invested in their relationship.
Naruto could be a protector figure. With his godlike abilities, he would be in a position to keep Korra safe from any major threats. This would create a bond between them, and Korra might grow to rely on Naruto, while Naruto would feel a sense of responsibility towards her.
Ichigo would likely be a bit brash at first. He's used to dealing with things on his own terms in the world of 'Bleach'. Izuku, on the other hand, would be very respectful and inquisitive. He'd probably ask a lot of questions about Ichigo's powers. Ichigo might be a bit impatient with all the questions but would soon realize that Izuku is genuinely interested. They'd start to bond over their shared desire to protect others.
One great 'Naruto' and 'Legend of Korra' fanfiction is 'The Bridge Between Worlds'. It combines the unique elements of both universes in an exciting way. The characters are well - written, staying true to their original personalities while also having new developments in this cross - over story.