Air China Questions

I will be flying Air China this week from HK —> PVG —> EU. Online it says I can have a carry on up to 5kg which seems terribly low. When I weighed my bag it was already 11kg so I would have to stuff 6kg worth of stuff into my backpack.

Does anyone know if this is strictly enforced? Like will they weigh it at the gate or check in counter? Cuz if not then that makes my life a whole lot easier (I have also never heard of carry on weight before).

Also, is there anything else I should know abt China layover? It’s two hours which is enough right? I also know the GFW will be there so I have a vpn just in case but I shouldn’t need it.

Thanks