I'd consider this an alternate timeline where the straw hats don't exist, or the things that led them to becoming pirates not happening at all. Like, Luffy never meets Shanks, Bellemere never dies in the hands of Arlong, Kuina never dies, Zef never neets Curly Brows, etc. You get my point.

Of course, going by the latter, we would have to change a whole lot of things. Everything leading up to Marineford and Marineford itself is essentially scrapped. Shanks still has his arm, and can be considered on par with Mihawk in strength, even stronger potentially. Fishman Island falls under Steroid Dude's control (tentative, don't know how they would fare without Straw Hats) ,Dressrossa is back to what it was before, and Dofflamingo is never captured, Ceasar is never captured, Smile factory is never destroyed, Kaido is never angered, Big Mom vs Luffy never happens...