So I've got a bit of a theory that I just thought about then about Zoro and Law. Law, despite and claims to German-hood, is very Japanese-coded in the manga (but so is everyone!) and I'll refer you to this post rather than blab about it. He's also often presented with Zoro (with tons of others too, but stoically with Zoro (some of the time, not all of the time).
Zoro not looking at all stoic there on the cover of Novel Zoro, but he really is more ronin (wandering samurai) than samurai (except he does have a master, but they're more equal). And Law's parallel is maybe the more underworld side of things that existed hand and hand in the water world etc., and seen with Hyougoro of the Flower in Wano (the yakuza leader), and Moonflower O-Cho. Zoro's boots are very un-geta, un-Edo-period like! Love one piece.
I also love the patterning on either side of their stories , Zoro's like a tatami mat, Law's far more geometric, but also in existence, especially in practicality of hapi coats and so on (but, maybe deeper symbolism. Will have to read the story!) I remember one early translation I read of the first Law novel saying that the Swallow Island boys addressed Law using 'oyabun', I think (could absolutely be wrong). The leader of a Yakuza clan. Similar wording is used for Jinbei. (I mean, Law was a runt, but he had mighty powers).
So both guys carry cursed swords, but Law's is unranked, and that also seems in keeping with moving about with the shadows and the not so overtly 'abide by a noble code' of the samurai. Zoro is not absolutely strict about this either, but works more within the traditions of the idea, having grown up in a dojo and given his clan, etc.
Anyway, just an idea. I know Law's the son of doctors, not born into the role he's adapted too/taken up. But, I also think these two (can) work in tandem this kind of way. In no way is it canon. Just a head canon.
Why do I do this stuff instead of sleeping. *sigh*. Also, I realise that Zoro's novel is ongoing!
I love that these two feature in the magazine edition dedicated to being: ""laid-back; light-hearted"), including focus on cute characters".