Since I don't know the exact 'the valkyrie new story', I can only guess. There would likely be Valkyries as main characters. They might be named after the traditional Valkyrie names like Brynhildr. There could also be a hero or a group of heroes that the Valkyries interact with.
The main characters in the 'valkyrie true story' include Claus von Stauffenberg. He was the one who played a major role in the attempt to kill Hitler. There were also other German officers who were part of the conspiracy. They all shared the goal of overthrowing Hitler's regime because they were opposed to the way he was leading Germany and the atrocities the Nazis were committing.
Doomsday Transformation: Valkyrie was an online literary work. There was no clear answer to the anime characters involved because this work was not officially authorized or recognized, nor was it widely adapted into an anime work. However, some anime characters that appear in works with the theme of the end of the world can be used as a reference, such as What Were You Doing at the End of the World? Are you free? Can you come and save me?" Bubu, Cory, Walnut, Qianxun, etc. in " Tokyo Ghoul ";; Jin Muyan, Lelouch, Lelouch Langlei, etc.; Allen, the giant hunter team in " Attack on the Giant ".
Obviously, Naruto himself could be one of the main characters. His determination and growth throughout the Naruto series would make him a great protagonist in a crossover. And for the Valkyrie side, maybe a well - known Valkyrie like Brynhildr could be a main character. They could have an interesting dynamic as they come from such different worlds.
The girl knight is surely one of the main characters. Besides her, there may be a mentor figure, perhaps an older knight or a wizard who guides her in her journey. And of course, there could be antagonists, like evil knights or dark sorcerers who oppose her in this valkyrie - related romantic story.
Claus von Stauffenberg was one of the main characters. He was the key figure in the plot to assassinate Hitler. His courage and determination led the Valkyrie operation.