The answer to this is no, edX is not a Chinese company. And although edX can be used in China, a lot of the courses and content are actually blocked in most Chinese provinces, making the online platform pretty inaccessible.
Instead, edX is actually American. It was created by the Massachusetts Institute of Technology (the MIT), and Harvard University, back in 2012. It is a non-profit organization, and as of 2021, the company has been bought by 2U, which is the current owner.
However, despite being American, the company operates mostly on a worldwide basis, with instructors and teachers from over 196 different countries, and with the platform being multilingual and full of diverse courses and institutions.