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I don't think it's an aversion if there's a demographic constraint.
If it were adult Detective Fiction, then it might be an aversion worth mentioning. But as it is, I'd say leave it out.
Speaking words of fandom: let it squee, let it squee.^^ I'd say, for my example I can't even be sure whether demographics is the reason; after all Detective Conan (for the same age group of the opposite gender), is practically a Body of the Week series to the point of Memetic Mutation.
Scientia et Libertas | Per Aspera ad Astra Nova
There's Always Murder and Never One Murder, which summarizes that murders are common in mystery novels. But how about when a mystery novel series has no murder? This is often the side effect of a demographic constraint.
The example in my head is the Tantei Team KZ Jiken Note series, which has a tween girl demographic. I have only read part of the novels, but my impression is that it won't have murder in the traditional sense (there's a case of euthanasia, though). The anime adaptation has no deaths, period. So, is it an aversion or an inversion of Always Murder? Or not belonging to any trope?