How it is 'false information' when it was stated in the manga that he turned Shisui into a black blade, which is something that someone who uses Busoshoku Haki could do and being known as a Sword God, which was something that was also mentioned in the manga.
Ryuma's caption was split into two different ones one when he was alive and one when he was deceased.
Ryuma Shimotsuki (One Piece) is hailed as a Legendary Samurai in Wano, preferring the Strong Blade Form, the strongest swordsman of his time for slaying a dragon. He wielded and turned Shusui into a black blade, turning it into one of the 21 Great Grade/O Wazamono Swords, then became known as a Sword God…
…postmortem his corpse was stolen by Moria then infused with Brook's shadow, postmortem he furthered his Gentle Sword Style, turning it into a more powerful and destructive variant used with his enhanced physique and Shusui.