Although a valid and understandable question to ask, it poses a significant number of physics and philosophy issues to be addressed. The first of which is the philosophical issue of Theseus’ Ship - at what point of substitution do we say that it is a different ship?
To convert and electron into a positron, you would first have to remove the negativity of the electron. That would require that you obtain the technology to actually hold an electron in place while you manipulate it … not currently possible. But even with that technology provided, an electron is made of nothing but negativity. Removing all of the negativity leaves absolutely nothing, no empty shape or form to be filled, but simply nothing at all. A positron can then be either created or more simply just moved into the former electron’s position. Then you could say that you “converted” the electron to a positron. But more likely, you are going to say that you simply replaced the electron after destroying it. It is actually just a matter of semantics, as is Theseus’ Ship.
But perhaps the more relevant issue involves the sizes of the kinds of things we have been discussing.
When I used a woman as something from which a propagation of PHT might occur, I was very, very far from referring to a “subatomic particle”. The word “particle” merely refers to anything very tiny, but in the realm of physics, a “subatomic particle” is not merely tiny, but ultra, extremely tiny and more importantly, the smallest possible physical stable form. And as tiny as women might get, they very, very seriously come no where close to the smallest or simplest stable entities within the construct of perception.
The human eye can see something about 0.1 millimeters width (10^-4 meters). An atom, and all atoms are roughly the same size, is about 10^-10 meters, 0.0000000001 meters. That is a difference of about one MILLION times smaller than a human eye could see. But guess what. A proton subatomic particle is roughly 100,000 times smaller than that at about 10^15 meters. But it doesn’t end there. An electron is roughly 1000 times smaller than that at 10^18 meters - 0.000000000000000001m.
That puts the electron and positron particles at roughly one MILLION times smaller than one MILLION times smaller than anything the human eye could ever see. The human mind cannot fathom such a range of size. And such is the case when it comes to the most fundamental, nearly nonconvertible, “particles” of PHT.
A single atom is made of many subatomic particles so far distant from each other than if you could actually see one electron, you could not see the orbited nucleus that is 1000 times larger because it would be 50,000 times further away. Molecules are then formed by atoms being fairly close together yet forming molecule chains anywhere from just a couple to trillions of atoms long. And from those are formed cells that are 10,000 times larger. And from trillions of those, is formed a woman. The difference in size and complexity is unfathomable.
The point is that the normal objects of perceived value, such as that woman, are invariably extremely complex combinations of much, much smaller intuitive PHT concerns, so small as to be undetectable by the conscious mind. They exist in the realm of the “subconscious” and even “unconscious” mind and are usually referred to a “an intuitive sense”. So whether the “subatomic” form of PHT particle could be converted is seriously irrelevant because there is nothing your conscious mind could perceive that comes anywhere close to being the most fundamental impetus for PHT evaluation. And that means that pretty much anything that you can perceive can be converted from a positive to negative PHT perception or vsvrsa. Smelly ugly things can become alluring attractive things … or vsvrsa. It is all a matter of proper programming.
Reversing the PHT charge of most concerns would be about like reversing the static charge of a Van De Graaff generator. The reverse charged particles or waves must be pumped toward the object while the formers are pumped away. Such is referred to as a “catharsis”, flooding the mind with a particular “charge”.