Not really. I think most the supreme blades will be from Wano.
There's only one supreme blade that has been etablished to be from Wano, and it's Fujitora's one.
But I’m not putting everyone who holds one above oden. Like if shiryus Raiu is one I’m not going to say he’s above oden.
So supreme grade blade are not portrayal even though Oda literally gave a non-swordsman like Whitebeard one even though nobody would have minded him a generic naginata... because of the assumption Shiryu could have one? lmao. Shiryu might also surpass Oden for all we know, depend when he fights Zoro. But until his sword rank is confirmed it's pointless to use him to degrade supreme grade portrayal.
You underestimate Oda if you don't think giving Fujitora (a non-Wano native) a supreme grade from Oden's land when the so-called epitome of a samurai didn't have one was just a whim from him. By doing it he directly compared Fujitora and Oden.
You have a preconceived notion of Issho strenght that forever cap him below Oden despite portrayal when the man hasn't been even close to use his full power once in the story.