> What I find interesting is that Apache Licensed software can be relicensed even in proprietary form (as long as you make it a derivative work, with your derivative bits with a proprietary license), thus the easy way out seems to be to have a non-US entity make a proprietary fork of AOSP. I do not see a legal reason why this company would not be able to sell AOSP to Huawei under these conditions.
IANAL, but: any such fork would remain a Derivative Work of AOSP in which Google would hold some copyright. When Huawei came to redistribute it, they would need licenses from all the copyright holders - this company, Google, any other contributors. Normally this does not matter: the Apache license states "each Contributor hereby grants You...", and You is defined as "an individual or Legal Entity exercising permissions granted by this License".
No doubt the US government can enforce whatever capricious fines it likes within the US. But I find it hard to imagine a European court finding Huawei guilty of copyright infringement for distributing Google work that came with a clear, simple license granting them permission to distribute. If the US government wants to say that Google can't grant that permission, that's between Google and the USG. And given that the Apache license states that the grant of permission is "perpetual, ..., irrevocable" and came with a copy of AOSP that Huawei has no doubt downloaded and read years before the current crisis, trying to revoke that permission now doesn't work either.