According to reports, owners of faulty Huawei Nexus 6P devices that have returned their device to Google have received Pixel XLs as replacements. Customers in some regions, however, are more likely to receive a replacement Pixel XL than others.
https://www.notebookcheck.net/Google-offering-Pixel-XL-as-a-replacement-for-defective-Nexus-6Ps.248476.0.html
I'm in North America and can confirm that I got a Pixel XL to replace my 6P.
Thanks for the confirmation, Cassie!