The Apothecary Diaries Manga, Vol. 3

We've reached the modern criminal investigations stage of Maomao's absurd detective journey. She doesn't have the tech of an episode of CSI but her scientific deductions are over the top and she even shows the actual professionals how to dust for finger prints.

It feels weird to say, but I think this would be more believable as an isekai story. A modern day truecrimes fangirl sent to an ancient China-like world.