I wouldn't be surprised if China refuses supplying WL-2. Supplying lethal weaponry now could be seen as an escalation.
It's weird that they'd be asking for them now when they've finally got full air control and not a week ago.
Recon or decoy drones in large numbers would be more appropriate. Anything Russian made would also be fine.
Speaking of which, what kind of weapon system China can supply and Russia can use right away, in about a month time? This news makes it sounds like a weapon system is something you buy from Amazon.com and ready to use the moment you unbox it. I call it fake news.
You can't. The technical training takes a long time. Not only do the Russians need to learn how to operate it, but they also need to know how to maintain it and integrate it into their military.
Unless the Chinese and Russians have been doing some secret joint training or something of that kind, I'd say this news is most likely fake and invented by the US to apply diplomatic pressure onto China. We'll see how China responds though. Their response needs to be worded extremely carefully since many things can go wrong. Examples:
If China were to say that they will never support Russia militarily, then a seed of distrust would be planted between the two by the US, and the Russo-Sino split will happen again.
If China were to say that Russia never asked China for help and tell the US to get Biden some diapers and to fix the Ukranian problem, that's a good response since it would preserve China's neutrality and future and present opportunities of cooperation with Russia.
If China were to say that Russia did ask for "help" and that they will look into it, then they would lose their political neutrality, thereby dragging them into the conflict.