I don't know, really.
It seems the US government is going to declare Hikvision equivalent of a terrorist organization. It bans any interaction with the entity globally (facilitated by threatening sanctions on everyone). It seems even its employees become something like criminals under US law. This is not an export control or import ban. This *should* have consequences. China should really ban all entities in China (regardless of their origin) from complying with these sanctions. Let's play the chicken.
The problem with banning entities in China from complying with this sanction is it will only help save some of Hikvision's business ties, but not help them grow their business relations in the future, so it doesn't help with their future prospects.
I have some ideas on how the government and Hikvision circumvent this problem.
1. Make Hikvision "not exist", by splintering it to multiple groups and obscuring its operations and employees. This makes it harder for US to execute their sanctions on the individuals.
2. Make like 100+ shell companies in China, with the sole purpose of rebranding Hikvision cameras to sell overseas. Make it a game of whack a mole for them.
As for retaliation, a highly damaging yet covert way of harming the US, is making patent protection and litigations intentionally harder for US business companies by prolonging the legal process for them to decades and making filling for them expensive. Eventually the Chinese companies will take the hint, that they can circumvent US patents with no short-term risk.