Assuming substance dualism exists for the sake of argument:
The only possible scenario I can think of where this would be the case is if we ever develop true AI, in which case substance dualism would not apply and the artificial consciousness can readily make duplicates of itself.
Even if we assume substance dualism is a thing, it stands to reason that there would be a co-dependency between the physical and the immaterial: to reproduce a snapshot of an immaterial mind with complete thoughts and personality, you must also reproduce the material "input mechanism" the immaterial mind has at that exact moment. And thus we enter the realm of physics. To replicate the brain (consisting of 100 billion cells), and also the neuron connections and a snapshot of their individual electric charge: the observer effect makes this impossible.
If we make the requirements less stringent and consider the immaterial mind capable of migrating between bodies, I would argue - again, assuming this is a real thing - everyday experience tells us that the memories and individuality of the previous "host" would be lost as no living person is able to perfectly remember their previous "host" personalities in detail.