TW for mentions of zoophilia and beastiality. This whole thing is a fictional scenario, so do not take this as serious.
This is a theoretical, fictional situation where someone has fully transitioned into an animal in every way (Internal organs, physical appearence, etc) and it affects their sexuality. Specifically towards nonhumans and humans. This is not real and is completely fiction.
Imagine this, someone has fully physically transitioned into a nonhuman animal, Every part of them is nonhuman and they are technically a nonhuman animal. now, what if i told you that they are attracted to other nonhuman animals? Would that be morally wrong? Would it be zoophilia since they were once human-shaped? Here is my opinion on the matter. (Lets call them, Being A)
In my opinion, this attraction would not be wrong. It is technically love between animals since being A has fully transitioned in every way into an animal, being that their physical body, internal organs, and mentality is that of a nonhuman animal.
Now, lets say another being (being B) is only physically transitioned into an animal, being that their internal organs are still human shaped and have a human mentality. I personally draw the line here, since being B has the mentality of a human, and internal organs of a human. If they were to be attracted to nonhuman animals, i would consider it zoophilia. Being B wouldnt have the reproductive parts of their species since they were human shaped before the transition, and being B would still have the mentality of that of a human, they should be aware that it is morally wrong to be attracted to nonhuman animals.
This also beings up another thing, would it be morally wrong to be attracted to being B? No, its much like being attracted to anthropomorphic animals, or furries. I am not saying that being B is a furry physically however. Now, would it be morally wrong being attracted to Being A? Yes. This would be considered zoophilia, because being A is fully transitioned and has the mentality of that of a nonhuman animal.
this also brings up another thing, lets say a being (Being C) has transitioned physically, and internally, but doesnt have the mentality of an animal. This is controversal because, they have the internals of a nonhuman animal, but think like a human. In my opinion, they cannot be attracted to nonhuman animals, but can be attracted to humans. Again, it would be similar to furries if a human was attracted to being C.