Chinese detective in exile reveals extent of torture against Uyghurs
cnn.com
cnn.com
You would have to convince at least the rich countries to stop trading with China and even then that could eventually lead to a war.
Realistically I think the US could start a soft war (blockade) with China (but they would have to be the one to start it) and try to starve it until it/the CCP collapses.