I am not sure about this as I've used Google translate to post in other local boards and had no issues whatsoever, and I remember other members using Google translate to write posts in our local board and again there was no issues.
If no one reports it and there is no local moderator to notice it, nothing is going to happen and the post will stay. I just took a look at the rules of Bitcointalk and I was right. It's not allowed according to Rule #27. It's not a big deal, though.
27. Using automated translation tools to post translated content in Local boards is not allowed.
https://bitcointalk.org/index.php?topic=703657.0