Sanji beat Arlong's RHM Kuroobi his first arc as a Strawhat.
When Sanji had just joined the crew and Zoro was on the verge of death, yes. One occurrrence doesn't constitute a pattern. If you want to favor that over the now very established formula that has been a thing for 20 years, be my guest. But anyone who's not utterly biased can see it's intellectually dishonest. You're grasping at straws and forcing an imaginary narrative.
The only times Zoro doesn't fight the right-hand man is when the second strongest opponent isn't the right-hand man, but he always fights the second strongest opponent regardless, the #2 either in terms of both rank and strength or just in terms of strength.
Jabra was the #1 option on his own team and the superior fighter to Kaku.
Yes, in Two Piece.
Absalom, while perhaps not the clear RHM over Hogback, unambiguously outranked Ryuuma.
Not only he was weaker than Ryuma, but he wasn't even taken down by Sanji. Nami took him down.
Kaidou made King his RHM when they met in their youth. Years later, he and Queen were nevertheless equals in rank to Jack, with the two of them clearly displaying a dynamic of equals to each other and seniors to Jack. It's very clearly intended they - the strongest opponents Zoro and Sanji have defeated to date - were equals or as close as possible to it by design. In fact, Oda's never been more explicit about the opponents of Zoro and Sanji.
You can word it however it pleases you and talk about how close they were as much as you want, it really makes no difference. King was both the RHM and factually the second strongest, so Zoro's opponent. It's not more complicated than that.
The only time when it was reasonable to think King would be Sanji's opponent, was before the start of Wano. Because back then, we didn't know whether Kaido had an even stronger underling that would serve as the Ace or Joker of his crew, the Shogun could easily have been an extremely strong samurai holding that position. And we thought Queen would likely be a woman. But once characters were introduced, there was no doubt left.
Nobody's opponents in this series fights anyone exactly like them.
Bruva, Sanji ripped off the Rokushi to expand his own skillset.
How does the fact Sanji later incorporated one of their moves to his style means he fights like them? Does Luffy fight like them because he learned to use Soru? Sanji couldn't even use Sky Walk when he fought Jabra, so that doesn't help your point. You'e dishonestly twisting your own frail logic – which is Sanji supposedly fighting opponents who fight like him when he does face them – to score points (yet still missing the mark).
Can but not always is the rule. Just like how bon clay did end up sanjis opponent with the shared parallels(there were more than just the kicking styles of fighting) you can also have matchups that dont share parralels.
The parralels are evidence... Just not strong evidence. Seeing a dark cloud could indicate rain. It does NOT mean its going to rain.
What shared parallels? Bon Clay was the third strongest and we saw him bicker with the second strongest, those were the real hints of him being Sanji's opponent.