Exports / Imports, % of GDP, 2016 Source: National Accounts at a Glance

https://data.oecd.org/trade/trade-in-goods-and-services.htm

                   Imports  |  Exports

   China             17%    |    20%

   US                15%    |    12%

China seems to be at a fair disadvantage on exports dependence, but you're right, China is far less export dependent than one might think. The devil is in the details of course, but I'd venture a guess that US imports would tend to be more discretionary than China's, but who knows.

Keep in mind much of china's trade with other nations is based upon the presence of US corporation's manufacturing and supply chains.