Well depends how we define legendary. Writing wise? Transcending the medium? DBZ for instance, while being an average manga or below average even, transcends the medium its in.
World renowned? Hardly. They do have some influential ones, prolly the most famous one recently would be Haruki Murakami.
It's a good question. Maybe OP will be brought up due to sales figures alone, but that shouldn't indicate quality.
Will any manga be put on a pedestal like that? It'd say no.
Is there manga out there that could be close to it? Maybe not Shakespeare etc, but I'd wager stuff like Monster and Berserk could have a shot.
I think the problem with manga is people (outside of the community) usually approach it from an artistic angle
Like Jojo’s didn’t make history because of the quality of its writing but Araki’s art. Inoue is a legendary mangaka with even some non-anime fans praising his
art rather than his writing (even if his writing is phenomenal)
I’d say that’s both a boon and a flaw of manga being a
visual medium
I think in the history books One Piece will likely have a spot similar to like Harry Potter. Where neither of them are praised for having never before seen levels of writing but they broke a lot of sales figures so it feels right to talk about
I had a professor in a media class that mentioned One Piece because he was going over the best sellers in each “category” (and this one was Japanese comic)
I think One Piece will fall under something like that