Pregnancy sex (as in pregnant bloated woman) is in fact among the lowest of niche porn just so were straight on that. As I said above I wasn't sure what you meant by impregnation as lots of people who are into the preggo sex use that word to define it.
But since we've established you're talking about straight ol vanilla sex that ends where it began there is still plenty of that. However it is spread across all the games she's put out and not dominant in any. Most people are use to the risky creampie porn as it's literally everywhere you go and we've all seen it a million times. Obviously anal is the same way but for some reason it seems to excite people more overall.
I personally don't prefer to stick my wick through the same backdoor shit falls out of due to certain risks no matter how good you clean the hole such as
chlamydia,
gonorrhea,
herpes,
hepatitis,
intestinal parasites,
HIV,
HPV, and
syphilis to name a few. It's simply not my thing but to each their own.
I'm more into the vanilla sex myself but anal tends to be among the most popular types of porn and who knows maybe the artist is into anal just like she seems to be into futas which are a big turn on for a pretty large audience as well it would seem.
If all she did was a ton of the creampie porn she'd probably lose most of her funding. It's the most vanilla of sex and as I said above we've all seen it done a million times. That's why there is futas in nearly everything and anal being another driving factor (no matter what game you play).
They simply spice up the game despite our personal preference on what we consider to be more enjoyable.
As for the offspring I dunno if she would ever bother trying to do something like that. It would have to be reskinned and rigged if it was a weird shape and she doesn't do that stuff. All of her models were done by someone else and even in wow when they have offspring from two different races the child tends to take on the looks of whichever they choose (Alleria Windrunner and Turalyon for example).
I just assume as with most interspecies based sex the dna is simply not compatible a majority of the time to even have the risk of pregnancy and kinda kills the point of it. However she did have a preggo nightelf in BiB by an orc and 2 drans by a tauren in this one so who knows what she has planned. But they would just grow up normal without any mixed traits from both parents so we'd never know.
If you're one of her donors maybe you could consider giving her some feedback on maybe changing how the ending scenes that do end in such a way have an option for which hole to finish in. It would just require her to change the dicks position while maintaining the same animation overall. It would require a bit more work but it wouldn't be too tedious overall.
Personally I believe that should be the path she should take at some point because more options is never really a bad thing. But I suspect we would be seeing a ton of reused animations/speeds reskinned which still wouldn't be that bad but would probably lower the overall quality of her work into mindless loop finishers for every interactive scene.
Good luck in your quest to find what you're looking for.