This is the most recent one I did on the subject.
https://worstgen.alwaysdata.net/for...abilities-before-becoming-devil-fruits.16856/
I spoke about Devil fruits containing souls from past users, and their wills being passed down through those devil fruits on a few theories back on OJ, but unfortunately those are lost to the times. The first time I ever brought it up was in this theory that I managed to save from back then. It's all the way at the bottom.
http://web.archive.org/web/20190607...s/the-one-piece-final-fantasy-connection.107/
The TL:DR version/summary of my thoughts on the matter is basically this.
Devil Fruits are said to contain spirits within them. When someone eats a devil fruit, their spirit somewhat intertwines with the devil fruit. When they die, the spirit of the Devil Fruit enters into the closest real fruit, retaining with it, some of the spirit of the previous user. So when a new person eats said Devil Fruit, they aren't just gaining crazy powers, but also inheriting the Will of the person/people who previous ate that devil fruit.