WARNING: THIS IS AN AU ONE PIECE WORLD. SOME THINGS WILL BE SIMILAR AND OTHERS WILL BE DIFFERENT. That also applies to characters and their ages from different animes. For example: All of Kenichi peers during his growth will be the MC's age instead of middle aged. The Kekkei Genkai clans are famous pirate crews and have influence in different parts of the world.
Power System
If you don't like the system, give me suggestions and I will make some changes
O, D, C, B, A, S, SS, SSS and further divided into three tiers as an example -O,O,+O
Ordinary - O - Ordinary people/Chore Boy (-O), Seaman recruit(O), Seaman first class(O), Seaman Apprentice(+O)
Genin - D - Petty Officer(-D), Chief Petty Officer(D), Master Chief Petty Officer(+D)
Chunin - C - Warrant Officer(C), Ensign(+C)
Special Jonin - B - Lieutenant Junior Grade(B), Lieutenant(+B)
Jonin - A - Lieutenant Commander(-A), Commander(A), Captain(+A)
Kage - S - Commodore(-S), some Supernovas(-S), Rear Admiral(S), Vice admirals(+S), some Supernovas(+S), Shichibukai(+S)
Super Kage - SS - Hashirama(+SS), Madara(+SS), Admirals(+SS), Garp(+SS),
Tailed Beasts - SSS - Fleet Admiral(-SSS), Yonko(SSS)
Skill and Item Tiers
White - Common - O
Green - Uncommon - D
Blue - Rare - C
Purple - Epic - B
Bronze - Exceptional - A
Silver - Legendary - S
Gold - Mythic - SS
Rainbow Divine - Divine - SSS
This is a Harem consisting of several animes that will all be incorporated into the One Piece world. The MC is gonna be "working" on rebuilding the Uchiha Clan in this world. There is gonna be some interaction with the main cast, but the story will mostly revolve around the MC, his wives, his kids, and his Clan.
The animes included are: Naruto, History's Strongest Disciple and obviously One Piece.
He will begin his journey with a few crew mates and it will quickly expand using his knowledge and his system. He will be a strong contender from the start and it will add changes to story.
His clan will be similar to clans in Cultivation novels. Anyone he deems worthy will be able to receive the Uchiha surname and maybe the bloodline, but that's for later in the story.
The harem is super extensive and some women will only be there to contribute children. Please do not expect every girl to get the same treatment. The main girls will be his first lovers and a few others. He will also slowly grab men that he deems worthy of joining his crew along the way.
MORIKO SENJU AND HIS FAMILY
Moriko Senju is a middle-aged Kenichi Shirahama (40). He is the only son of Hashirama and Mito Uzumaki. Miu Senju is a middle-aged Miu Furinji(40) and the only granddaughter of Hayato Furinji. Their children are Kisuke Senju, who is a 20 yrs old Kisuke Urahara, Tsunade Senju is a 18 yrs old Tsunade, Asagi Senju is 16 yrs old and looks like Asagi Aiba in Strike The Blood, Asia Senju is 15 yrs old and looks like Asia Argento, Nawaki Senju(12) is the same age when he died in Naruto, Amane Senju (5) is the unnamed little girl that Miu and Kenichi have at the end of History's Strongest Disciple in the manga.