Apothecary diaries
The writing seems too simplistic. It doesn’t give any depth just maomao doing maomao things. No describing the world or characters just maomao did this, that, the other.
This reminds me I was reading some LN that wasn't particularly good. I think it was Isekai Walking? Anyways, he receives a brooch from a bishop that proved he was a friend, or something, and it was described as something like, "a very nice brooch," which I thought was light on detail, even for my low expectations.
The other thing your comment reminded me of was the time I tried to read Harry Potter and the Philosopher's Stone in Japanese. It was unbelievably dry. It seemed like just a bunch of statements with no life behind them. I spoke to some other people about it, and apparently, that can be a fluency thing. If you're not used to a language, the charm behind the writing can easily be lost in translation. I'm not saying that's the case with the Apothecary Diaries, just that your description reminded me of my experience.
I haven't read Apothecary Diaries yet, but I can imagine that if they're written from Maomao's perspective, then it's not surprising if it's very simple, because her personality that I know from the anime is very dry.