I'm working with a group in China, and we were discussing the following question, which I would like to ask here too:
Question: Is it better to write a paper in Chinese, then translate it into English, than to write it in English to begin with?
Of course, this question is not limited to Chinese.
Both myself, and the (Chinese) professors in the group I work with felt rather strongly that writing in English to begin with is better. However, we didn't manage to articulate any tangible reason as to why we feel this way (mostly just out of intuition). Hopefully the group here can offer some meaningful insight one way or the other.
Note: I'm sure if I leave out the specific context, I'll receive a comment asking for it. So, in our case, the context was students writing technical scientific research papers (in computer science).
I have a pretty good level of English. However, my Spanish is way richer and I can elaborate ideas and concepts with deeper arguments and a more generous vocabulary.
If I need to prepare a short blog article or a Stack response, I just do it in English. But if I must write a long document, I use to think of it in Spanish to come up with better ideas.
Otherwise, I feel that the result is quite basic from a language point of view.