This is exactly what happened to us. We received a mid 6 figure bill for things we imported before any of this was even a law.
Constitutional violation, under the "ex-post-facto" part.
This SHOULD be fightable.
Are there any known asic chips manufactured/produced in China?
No - they don't have the capability of producing 16nm or smaller chips at all.
I'm not sure if they can even produce 28nm.