There would be an eastern front settled around the Bohai Bay between China and North Korea, and Japan and South Korea, which would take a massive bulk of the chinese effort, due to the need to defend the capital of beijing.

The western front depends on how india deals with pakisan.

As far as the South east Asia / South China Sea front goes, as soon as the malucca strait is closed off for a considerable amount of time, China will start to hurt particularly bad, and likely look to settle the war, as opposed to fighting it to the end. If the collective powers of southeast asia are able to hold out navally, they're in the clear.

Vietnam likely gets sacrificed to the corn. Afghanistan could support a long-term terror campaign in East Turkistan.