In short: nope, it actually enhances it. Here, magic is a part of every living thing, it's certain individuals who have the willpower to use it (kinda like jojo stands) and thus create a sort of "soul gem" to transform do so at full power. Since it's part of one's soul, as long as they have at least a fraction of their body left it can be used. The whole cyborg thing in this au is seen as an opportunity to enhance/control the physical aspect and capacity of one's magic