Some people get upset that someone on a 'non-immigrant' 'temporary employment' visa can apply for permanent residency, although that is allowed by the H1-B program.

Otherwise, one could immigrate through a different visa; there are some employment visas that are explicitly intended for those with intent to immigrate. Or like a family or lottery visa, I guess.

I think it's possible to have a permanent residency application sponsored by an employer from abroad, but especially if the candidate is from China, India, Mexico or the Philipines, the timelines make even less sense than H1-B timelines (submit your application in a two week window near the beginning of March, for the chance to start in October). I don't know too many places that want to commit to a hire that can't start for 7 months, although it's not unreasonable for those on post graduate visas with work eligibility.