What the Chinese are doing is they have long term supply contracts with Australia, the US and probably others. So the companies have to supply China, even if they could make like 5 times as much selling to Europe. But the Chinese utility customers they can choose to not take delivery, and instead sell their LNG to Europe.
So talk is China is reducing production of some manufactured goods or upping coal production, because the profits are so huge in selling their contracted LNG elsewhere.
The companies supply China in these long term contracts they don't mind though. Because they like signing 30 year contracts with China at fixed prices. Where the prices are enough they make guaranteed money and pay for all the huge infrastructure investments.
Potentially China could import more natural gas from Russia, then sell the contracted rights to the LNG to Europe. But I know little about how much capacity there is in the natural gas pipelines from Russia to China.
Russia 100% has to be constructing more pipelines to China though. China will pay high prices for however much natural gas people will send them.