Comment by samus

I see a high risk of idioms getting butchered. It's usually a good idea to translate into English and fix that up first. And unless a native-language editor revises it, there might be sentence structures that feel unnatural in the target language.

A classic issue is dealing with things like wordplay. Good bilingual editors might be able to get across the intended meaning in other ways, but I highly doubt translation software is capable of even recognizing it.