The details of this replica Bleach sword should accurately match the personal weapon of the story’s main antagonist — Sousouke Aisen, one-time captain of the 5th Division Soul Reapers and the creator of the Hollows.
The sword called Kyo-ka Suigetsu presents its ordinary form as a katana with a distinctive hexagonal tsuba or blade guard. Without any other obvious decoration, the only distinguishing characteristic of the katana in its physical form is the distinctive green ito or woven cord grip. The “mirror flower water moon” sword possesses the intangible power of illusion, and when enemies see it, their perceptions become controlled by an unbreakable hypnotic spell.
That’s more than a little confusing, considering that some photos of the Kyouka Suigetsu sword depict it as having a blue ito instead of a green one, but since confusion is the sword’s primary power, that may be acceptable to collectors of Bleach manga weapons. The physical form of this replica sword is otherwise accurate, 40 inches long overall with a 27-inch blade of high carbon stainless steel and a traditionally styled saya or scabbard of lacquered hardwood. The 440 stainless steel blade isn’t tempered for combat use but will suffice for display or costume purposes.
All weapons in the Bleach manga do have physical and spiritual forms, and replica weapons try to reproduce only one aspect of the swords. The accurate form of the “complete hypnosis” sword may be one of the more difficult to pin down.
See the Jushiro Ukitake sword for another example of a Bleach replica weapon.