What would be the effect of a lobe-swap?

The first human head transplant was completed in 2017, which means it is either now or will be soon possible to transplant lobes of the brain.

Currently, one of the treatments for severe, life-threatening epilepsy is a lobectomy, in which fully one half of the brain, an entire temporal lobe, is surgically removed. This is not only survivable, it has surprisingly little effect. This is due to the plasticity of the brain, which is capable of rewiring itself on the fly and adapting to new conditions or routing past damage, and even reassigning parts of the brain to perform new duties.

My question is, what do you believe the effect would be of removing one lobe of your brain and swapping it with that of someone else? There is every reason to believe that the brain is capable of adapting to such a situation, at least physically. What I’m curious about is what the psychological and possibly spiritual effect would be.

Would you become one body with two minds, each with their own separate identity? One of the less traumatic treatments for epilepsy than lobectomy is severing the corpus colossum, the major connection between the two lobes of the brain, and this has been known to produce some… interesting effects, such as alien hand syndrome.

On the other (alien) hand, you have cases like Abby and Brittany Hensel, conjoined twins with two heads who share a single body, and there is evidence that each of them can feel the other’s thoughts, at least on an unconscious level. This suggests that there might be two identities but with deep fundamental overlap, each identity merging seamlessly into the other so that there’s no discrete line separating where one stops and the other begins.

The third option would be the total melding of both identities into something entirely new, an identity which combines both previous identities and leaves nothing of the originals. We often see this kind of thing happen with major strokes, where insult to the brain results in major shifts in personality, talents, and even languages in the person affected.

Another possible outcome would be total dysfunction. Chaos and complete obliteration of both identities, unable to handle such extreme conditions.

Given your own understanding of neurobiology, psychology, philosophy, and theology, what do you believe the effect would be?

As a bonus question, assuming it was a full swap—that is, person A gets a lobe from person B, person B gets a lobe from person A—do you think the effect would be necessarily identical for both individuals?

As a bonus bonus question, would the resulting person have one spirit or two? If two, and if this case was a swap as in the question above, then we now have four spirits where we originally had two. Where did they come from? And would these spirits assume the sins of the previous identities after death, or would they get a clean slate?

As a bonus bonus bonus question, how would the law regard such a person? Assuming one of the people involved in the swap had committed a crime, would either of the people, both, or neither now be guilty of the crime?