Honestly, she's quite the adventurous one since day one, so to me it wouldn't seem off-character for her to propose some kinkier sharing experiences. But there's no hint so far of her becoming a cheap whore (even if she's the one suggesting some of the encounters, she will obbey what MC decides because she loves him above all) and what I get from Dev's comments is that the paths will stay balanced (1 sharing / 1 non-sharing alternative scenes). So I think there's no reason for you to worry.
Well, even if she is adventurous, she is with the MC, this is like real life, you can be very adventurous and spicy with your partner, but you are not going to be with someone you just met, no matter how much you attract, much less are you going to tell your partner hey, what if you let me suck it while you watch?
For example, the first share scene of the game, she says that you have a public, but she does not say hey, let me go suck it off, not much less, it is the MC who decides what to do in this scene, unlike, for example, the scene with the hunter , which I find VERY BAD written and carried, since it seems to me something that Kat would NEVER really do or say (oh yeah, let me fuck him so he can learn a lesson .. seriously? what a lesson? that being an idiot as he is he can end up fucking amazing girls like you, Kat?)
My point is that I don't want any path that involves Kat to end up becoming an Anne 2.0, firstly because Kat, as I have said, seems sooo well written to me, and it would bother me, and secondly because from my point of view it would be an alternative to what Kat really is. The swing scenes with couples close to MC and Kat don't really look bad, but the share with strangers and idiotic men like hunter, trevor and street randoms .. sorry but that wouldn't be like Kat, no matter how much the dev gives you the "good" option not to share in the other choice, I think it would be a very bad way to create alternative content for Kat imho.
Sorry if I sound a lil bit rude or something like that, but srsly, I love so much Kat and I dont want a bad way for her, in any of her routes because she deserves a goood good way <3