Nope, none of that uses symmetric keys >256 bits. Nothing does. The only reason to go >256 bits is if your crypto is getting attacked by an adversary with a Dyson Sphere-sized quantum computer, or an adversary that's found a way around the laws of thermodynamics. Either way, you have big problems.
Of course not - they are free, you don't need to import them.
If you meant "Cisco VPN gateway" then yes, and I wonder if China is actually going to prevent import of cryptography hardware that's known to be broken or backdoored.
It's a legit concern given the Crypto AG gate that happened a while ago.
Where the so called reputation of swish neutrality was destroyed, if i'm not mistaken the German and American Intelligence agency had compromised the encryption hardware.
What makes you think that cost (or lack thereof) has anything to do with whether or not something is imported? The two things are completely orthogonal.