For this question, I'll pose it in the form of an example since it gets confusing otherwise
Say I am playing a level 17-20 wizard who wants to use the Clone spell to become immortal, but want a safe place to hide the clones. In line with this, I decide to use the Demiplane spell to create a demiplane, and create a clone inside of the demiplane (using wish to avoid dealing with the duration of demiplane). I then leave the demiplane, and eventually die at some point after the clone has matured.
At this point, my clone activates, and my wizard's soul re-enters it. At this point, while the wizard's soul is native to the plane they were born on, their body was created in the demiplane. As such, for the purposes of such spells and effects as Banishment that vary in effects depending on a creature's native plane, is the wizard native to the plane that it's soul comes from, or to the demiplane that it's body was created in?