>>64086380
as said, it wont.
China is self-sufficient in grains and basedbeans are used for pig feed, which will be rationed during times of war. China's other overland trade partners are also ready to supply alternative animal feed like sorghum and even wheat to China, like Russia is currently doing.
There wont be any starvation in China during wartime, since China has an industrialized agriculture nowadays that is actually prone to overproduction and deflation.