Right now I'm bored with One Piece, and as I've said before, I don't think I'll ever get around to writing this sequel. Still, I've received a lot of PMs asking for at least a synopsis.
I'll do you one better: here you have the main points of the chapters as I 'planned' them. If I ever get around to writing it, it'll be something like this.
ch1
3rd person
Randevoux on an island in the New World, escorted there by Whitebeard's people
The Moby Dick is the new captain, uses the naginata of Newgate
ch2
3rd person
News Coo, Supernova reactions, new bounties
Beginning of training for every member of the Straw Hats, Coby talks with Chopper and Sanji about preparing for 'metamorphosis' once he eats Whitebeard's shadow
ch3
eating whitebeard's shadow (aftermath, learning proper Haki, blossoming)
Using the transformation to justify lack of foreknowledge:
"It looks like I can no longer see the future."
"At a time like this?"
"It will make everything more fun."
news coo: Blackbeard with Marines attacks Amazon Lily (implied he takes Hancock's power)
ch4
1 year timeskip,
sword-fight with Zoro
sparring duel with Luffy (forcing the 'blossoming' of Haki)
News Coo for cliff-hanger
ch5
News Coo: Ace takes Wano (Yamato's freed), Kaido destroys the Moby Dick, Ace takes over, Kaido retreats somewhere
Sabo comes to say hello to Luffy, mushy chapter, obscure warnings about what will happen with the reverie
Sail with Sabo to Dressrosa (use his mission to justify turning back towards the beginning of the New World with an Eternal Pose instead of adventure for adventure's sake)
ch6
Gura Gura no Mi or Rumble Rumble no Mi as the prize for the Coliseum: first option to introduce Blackbeard quickly, second to keep closer to canon
Fujitora protecting Doflamingo: Coby vs some of Doflamingo's officers, Zoro vs Fujitora (swordsman duel, actually cool)
Sabo investigating
Sanji wins the Rumble Rumble no Mi for Nami? (fanservice for those that still care about Oda's opinion)
background stuff to keep everyone busy
ch7
Toys returned human freed, brief voyage back through Fishman island and to Sabaondy to get people back to their islands (Coby secretly kills Hody&co), separation from Sabo
Rayleigh's pov: meeting with Barrier Guy, punching a celestial dragon, freeing the green-haired sister of Hancock Sanji fighting the CP in place to keep her compliant
ch8
Razing Sabaondy, Nami dictating the stealing, while Luffy-Coby vs Kizaru
PX-machines, marines, and random pirates as opponents for the others
OP-Brook large scale music-illusions, and going over the power-ups that I passed in the background until now
ch9
Brief chat with Rayleigh and sail away,
News Coo about Trafalgar Law dropping his title to raid something important
true beginning of the New World: Punk Hazard, Coby eats a dragon's shadow: can now make wings and fly, Cesar escapes (decide if to go along with the fate-bullshit or not, who cares about Momonosuke and Talk-from-my-ass samurai?)
Smoker gets involved, Coby steamrolls him, Aokiji casually strolls in
ch10
Coby points out how suspicious Aokiji's defection is, and fights ensue
Stuff from Aokiji's belongings, eternal pose to wherever I need to push the plot forward (maybe Blackbeard?)
ch11
Gunning for Big Mom, Cody calls dibs on Kaido for whenever they meet him
Tottoland arrival, Lola's arc (fights the long-necked swordswoman, Sanji vs Mochi-guy, Luffy vs BM, Coby vs buncha baboons)
alternative
Zoro vs mochi guy
Sanji vs candies man
Mikita steals poneglyphs
Merry vs Cracker
Brook overtakes Big Mom's sword, fights smoothie
Luffy vs Big Mom
ch12
closing up the fights, showing Nami figuring out how bullshit her power is, three-eyed girl makes a mess with Zoro's memories because he's an idiot and doesn't fight against Smoothie
Zoro gets lost with wonky memory
Sanji manages to seduce the three-eyed girl so he finally can have sex somehow, she promises to restore Zoro's memories when they find him
ch13
Zoro vs Shanks by chance and loses
Kid's coalition with music long-arm guy and Hawkins (they gun for the Straw Hats because they're the hottest new players on the sea)
Trafalgar accepts Cesar on his crew (obviously takes his heart)
ch 14
Everyone on the Red Force is drunk off their ass, nobody recognized Zoro until he wandered off
News Coo about Zoro, Straw Hats reactions while they get on a sky island, plans for vivre cards and for Usopp to bullshit them with his power to have a secure way to track everyone
ch15
Random adventure on sky island
Kid&co vs Zoro, he wins narrowly, sails off
ch16
News Coo: Blackbeard drops his position, he has found the crew he wanted in the meantime
Trafalgar&co capture Zoro, intention to ransom him for Poneglyph, Trafalgar plans to kill the Straw Hats (brief pov to explain his unresolved anger issues since Luffy and his people took off Doflamingo's head)
Blackbeard moves vs Whitebeard, allied with Kaido?
ch17
news coo with new bounties for everyone
Law makes contact with the Straw Hats, organizes stuff so that there is also Eustass Kid&co
ch18
Green-haired barrier guy vs Cavendish for something absolutely inane, they stop because Law organized for Kidd's forces fight against Straw Hats to be recorded and put on air to get a favour from Morgan, aiming to get set up as another of the greatest on the sea now that Big Mom's gone
Vinsmoke trying to stop the Straw Hats because they made the deal with BM fail, they get trashed, Renju either joins or dies meaninglessly
ch19
Kidd&co vs Straw Hats, Morgan tells Nami about Law's location (he knows about Blackbeard and Kaido, and has better things to do than to cater to Law in madman mode), with Mikita and the three-eyed girl she tracks down Law
return memories to Zoro
ch20
Whitebeard's people vs Blackbeard and Kaido
Kaido betrayed, Burgess with his fruit?
dead Moby Dick, Marco dies, burns and is reborn as a child, Ace takes over
Kidd&co trashed
ch21
Zoro with Mikita, three-eyed girl, and Nami, destroys Law&co
Aftermath of the fights, Fujitora smacks down both cavendish and the green-haired barrier guy,( to the rebuilt Impel Down?)
ch22
Meeting with Ace
Interrupted by Mihawk
ch23
Zoro Mihawk duel
ch24
Exchange of news with Morgan (and video of the duel from Usopp's modified transponder snail)to get the location of Blackbeard for news about (killing Zou because he can)
news coo, reactions
ch25
reverie, Sabo captured (begin subplot, no reason not to follow Oda unless he pulls more bullshit)
Ace settles the new territory of the Whitebeard, the daughter of Oden becomes the boss of Wano
Straw Hats gunning for Blackbeard
Kaido vs Shanks
ch26
Blackbeard vs Luffy over Zou's corpse
members of BB vs Straw Hats
ch27
victory (party, healing, recruiting of animal-people?) (if following the fate bullshit of Oda allow Blackbeard to escape)
news coo with bounties and news about Shanks (killed Kaido)
ch28
Shanks vs Luffy (plus crews)
Usopp fights off with Franky the marines from interfering (the plant admiral), and becomes a brave warrior of the sea
ch29
victory- Mikita and Lola create the best chocolate sweets ever, Mikita's dream as best chocolatier wins
Laugh Tale, with local plants Chopper creates a panacea, Robin finds the truth of the Void Century,
ch30
bullshit aftermath of the reverie just for the sake of drama, news about captured Sabo
Luffy (now King of Pirates) guns for the World Government
ch31
Coby tears down Marejoys while Luffy wants only to rescue Sabo, helped by Ace
Epilogue: breaking of the Red Line, all seas intermix.
Lola's pregnant so her dream becomes true (somewhat), Sanji gets the All-Blue, Brook gets reunited with Laboon, Coby finds Vegapunk and learns everything about Devil Fruits, yadda yadda yadda
setting up of the next Era (Fairy Vearth? Space Pirates?)
the end