From the films one can infer that Sith essence transfer works in the sense that your spirit/essence inherently leaves your original body that is killed by specifically another Force sensitive and your spirit/essence goes to, for example, Palpatine’s clone body or Rey’s or Ben’s body 'cause you will it to, Palps knows where those are specifically.
I disagree with the inference, but whatever. Palps says, “Kill me and my spirit will pass into you.” Not “my spirit will pass into my clone”.