Adding this to the OP. The agenda isn’t dead until Oda kills it. Lol
@BaboonMihawk pointed out in his thread that Aramaki Gennai, the main character from Ronin Gai of which Ryokugyu is based off of, was rumored to be a superb swordsman, but no one had ever seen his sword skill before with the exception of his lover.
This would seem to matchup with Ryokugyu who appears to be a swordsman but has yet to reveal his skill with the blade.
And by drawing Ryokugyu with a black blade, Oda could be referencing Aramaki’s hidden extreme prowess with the blade.
#FuckToei