Obviously, Ahsoka is one of the key characters. And the members of the Ghost Squadron would also be important.
In this fanfic, Ahsoka is the main character that everyone is interested in seeing interact with the Ghost Squadron. The Ghost Squadron itself is made up of several members. There could be a pilot who is excellent at flying and navigating, a mechanic who keeps their ship in top shape, and a strategist who comes up with plans. All of these members, along with Ahsoka, would be the key characters in the story, and their interactions would drive the plot forward.
Well, perhaps Ahsoka and the Ghost Squadron could team up to fight a common enemy. Maybe they'd share their different combat strategies and learn from each other.
The main characters would be Ahsoka and Ezra. Ahsoka has seen so much in her life, from the Clone Wars to the fall of the Jedi. Ezra, on the other hand, is just starting to understand his powers. Their meeting could be a turning point for Ezra's growth. Also, Hera is important as she is the one who holds the Ghost Squadron together. Her interactions with Ahsoka, especially in terms of strategy and leadership, could be a major part of the fanfic. And of course, Kanan, who can bridge the gap between Ahsoka's more traditional Jedi knowledge and the unorthodox ways of the Ghost Squadron.
In this fanfic, it could start with the Ghost Squadron being in trouble. They are outnumbered by a large Imperial force. Ahsoka senses their distress through the Force and comes to their rescue. After the battle, they exchange stories. Ahsoka tells them about her time with Anakin and the Jedi Order. The Ghost Squadron members share their own experiences fighting against the Empire. They then decide to travel together for a while, with Ahsoka helping them with their ship's repairs and combat training, and they in turn introduce her to new allies in the Outer Rim.
There might be a rookie in the squadron who is also a main character. This character could be learning the ropes, making mistakes, but also showing great potential. Their journey of growth within the squadron can be a central part of the fanfic.
Obviously, Luke Skywalker and Ahsoka Tano are the main characters. Luke is a key figure in the fight against the Empire and in the revival of the Jedi Order. Ahsoka, on the other hand, has a long and complex history within the Star Wars universe, having been Anakin Skywalker's apprentice and later becoming a key figure in her own right.
Obviously, Peter is one of the key characters. And then, of course, the Avengers members such as Iron Man, Captain America, Thor, Hulk, Black Widow and Hawkeye are likely to be key characters as well. They are the ones Peter is going to meet and interact with in the fanfic.
Chopper, the feisty astromech droid, is also a main character. He may be grumpy but he has his own charm and is often involved in the squadron's missions, whether it's helping with repairs or providing some comical relief during tense situations.
The key characters are obviously Naruto himself and the members of Team Minato. Team Minato consists of Minato Namikaze (Naruto's father), Kakashi Hatake, Rin Nohara, and Obito Uchiha. Naruto is the main character from the original series who travels back in time or through some other means to meet his father's team.
The main characters would be Ahsoka and probably a military strategist. The strategist would be constantly trying to figure out how to best utilize Ahsoka's skills within the military framework. And Ahsoka would be trying to understand the military's way of doing things, leading to a lot of interesting interactions between the two. There could also be a young soldier who looks up to Ahsoka as a mentor figure in the story.
Anakin Skywalker is a popular choice. Their relationship as master and apprentice in the Star Wars universe provides a lot of material for fanfics. Another popular character is Rex, as they have a history of fighting side by side in the Clone Wars.