Whole Cake Island set up Sanji vs Big Mom, and Wano set up Zoro vs Kaido.
Both of these fights will still happen: in Wano Act 4. I also believe that Zoro and Sanji beating Yonkou deserves rewards, so, what better reward than a new way for the wings to soar, that won't make them sink?
Figarland Shamrock has shown the easiest way for a Swordsman to gain an upgrade: have your blade eat a Devil Fruit.
Oda's even stated that Zoro's Fruit, if he had one, would be Wado eating Kaido's Fruit.
Zoro's father, Arashi, was said to be killed by pirates in battle. We know Zoro's lineage is from Wano: if Zoro's father is anything like Zoro, and heard from citizens fleeing Wano that Kaido had taken over... remember Ace going to Wano? There ya go: Arashi traveled to Wano to fight Kaido, and died.
Once Zoro realizes this, he'll take Kaido's head in Wano Act 4. I believe Linlin's Soul Pocus will unleash some crazy business, so, it's possible Zoro meets the ghosts of his past, literally.
Then, there's Sanji and Marco: I firmly believe the Whitebeard Pirate Remnants will fight Blackbeard again, and Marco will sacrifice himself to save Sanji, or some other Straw Hat/ally.
Too many death flags on the man; let him go up to see Newgate and Izo. IMO, Marco's Awakening includes a cool feature: he can "Revive" his Fruit into the individual of his choosing.
So, the Phoenix Fruit will be "reborn" inside Sanji; giving him Flames of Love, that heal his allies, and the women around him. Using his newfound Adv CoC and Phoenix Fruit powers, Sanji will kick the evil out of Linlin, without harming her; namely, kick out the remnants of Mother Carmel's Soul, while also freeing the Sheephouse Children's Souls, and letting them become Homies. Bonus points if Mother Carmel becomes a literal Mountain Homie.
Sanji: "I am a warrior of science, and an ally to all ladies! I am the Science Warrior of Love!" probably
These Devil Fruits upgrades will allow Loki to join the crew, by making Sanji and Zoro stronger, without making them weak to water.
Sanji with Marco's Fruit becomes a Cleric Tank Powerhouse, capable of healing allies a good deal and healing himself greatly with his Fruit, possessing ridiculous natural bulk + Exoskeleton + Raid Suit, combined with Mythical Zoan Endurance and Regeneration.
Sanji's Raid Suit will be based on Sora, Knight of the Sea, and be built by Franky and Lilith in conjunction. Vegapunks stays stunting on MADS: Lilith will make a Raid Suit better than anything Judge could, that increases Sanji's Flames, speed, and Invisibility.
Sanji with this suit will become a true defensive powerhouse capable of unleashing furious amounts of damage as well. His overall damage output will be below Luffy and Zoro's, but his defensive and speed will be far beyond theirs.
Zoro, on the other hand, will know how to use Kaido's Fruit well, as he's fought Kaido directly in both Full Zoan and Hybrid. Kaido's Basic Techniques with his fruit are already monstrous, like Boro Breath: once Zoro is able to use the Flaming Torch Dragon, he will be an utter monster.
Zoro can also possibly have Wado turn into Hybrid Dragon form, and fight beside Zoro as an ally, like a Familiar/Summon.
Finally, since Wado Ichimonji is the blade Zoro typically uses in his mouth, Wado can transform into full Zoan Dragon form in Zoro's mouth, while Zoro's arms are still free to use two-sword, Nitoryu techniques.
Zoro being able to use Kaido's Dragon techniques like Boro Breath, Demolition Gust, as well as Flaming Torch Dragon, which nearly defeated Luffy's strongest Gear 5 attack, Bajrang gun, while also dual wielding Enma and Sandai Kitetsu (or Shusui, which I think he will take back), will make Zoro a ridiculous glass cannon burning through Haki and Stamina to unleash utterly insane amounts of slashing and elemental damage. Since Zoro can already create flames with his blades, he's probably even more primed to use these Dragon techniques than most Swordsmen.
Furthermore, I would be very happy if Zoro's Observation go to the point where he could talk to Enma, and Oden/Kaido as well, through Enma.
This would allow Kaido to "survive" in Zoro's blade. Bonus points if Enma goes back to Momo, and Kaido teaches Momo dragon shit via Enma, while Zoro gets Shusui since he's Ryuma's descendant, and got Ryuma's approval to use it, Nidai Kitetsu, and Wado Ichimonji.
Having their Raid Suit/Sword respectively eat Devil Fruits, rather than themselves, allow Zoro and Sanji to still be of use in water.
Sanji's Blue Walk is an impressive skill, and even Arlong Park Sanji had impressive underwater feats.
Zoro was able to more or less one shot Hody Jones underwater, and, while Hody was New World weak, he wasn't WEAK.
Zoro also blew up a ship in Sabaody and then swam back to shore.
Both are very useful underwater, and this allows them to not give up those strengths.
With these Fruits going to Zoro and Sanji, Loki is much more likely to join the crew
@Mr. Reloaded @DarkestKnightofSpoilers @Peroroncino @Tyki_Mikk @Bisoromi Bear
Zoro and Sanji with Adv CoC and Ryuo + Mythical Zoans are Yonkou level characters, change my mind
https://comicbook.com/anime/news/one-piece-creator-perfect-devil-fruit-for-roronoa-zoro/
The Straw Hats will surpass the Rocks Pirates and Joy Boy and become the strongest Pirate Crew of all time!!!!!!!!!!
