As far as Edea's hands goes, the Ultimania Guide makes it clear that misuse of the Witch Embodiment (Black Magic) results in physical deformities. This is why she has those elongated claws in place of her fingers, and why those veins are growing across her face.
Further, that's why Adel's body is so deformed, and the same is the case with the Witches encountered as SeeD travels to the future.
