Silver Samurai x Katana (Requested) + Story

Soul Samurai's Origins by MoonKnightFan101:
Tatsu Harada grew up in Japan into a family of the criminal Clan Yashida, where she mastered the attendant disciplines of the medieval samurai and became an Olympic-level martial artist who sought employment as a warrior for hire. Eventually, she met and fell in love with a man named Maseo Yamashiro, and the pair had two daughters, Yuki and Reiko. Tatsu soon retired from the Olympics and for a time, she lived a happy life with her family. However Maseo's brother Takeo, a member of the Clan Yashida, soon grew jealous of his brother's relationship with Tatsu. Fearing Takeo's wrath, Tatsu fled to the countryside, in a vain attempt to avoid the murderous brother. In the end, Takeo found Tatsu and her family and burnt their home down to the ground. Using the sentient Soultaker Muramasa Blade, a mystical Japanese artifact, Takeo butchered Tatsu's husband and two daughters. In an attempt to avenge her family, Tatsu attacked the murderer. However with the Soultaker, Takeo was able to overpower Tatsu with relative ease. However, before he could strike a killing blow, the Soultaker had a change of heart and chose Tatsu as its new wielder. With the blade, Tatsu killed her brother-in-law, avenging her family. Tatsu soon realized that her husband's soul rested within the blade, along with all its other victims. With the burden of the souls on her back, Tatsu was reborn as the anti-hero Soul Samurai, who would hunt the Yakuza down, in an attempt to avenge all those who had been killed by Takeo.

Both characters belong to Marvel and DC respectively.
This combination was suggested by Boo-Comics