As far as I can tell, there is a movie by Yoozoo that was finished in 2015 but never released: https://en.wikipedia.org/wiki/The_Three-Body_Problem_(film)
There is a Chinese produced series made by Tencent that (I think) is still in production: https://www.straitstimes.com/lifestyle/entertainment/china-t...
And there is also an animated series by Bilibili that is scheduled to come out in 2021: http://www.xinhuanet.com/english/2019-11/18/c_138564215.htm
Is the Netflix version additional, or a replacement for one of these?