Ridiculously simple: Set out to hire a good programmer (as opposed to "a Go programmer"), and make it clear in the job description that they're expected to spend the first 6 months learning Go on the job.
You end up demonstrating to employees that you're willing to give them something useful, gain loyalty; AND end up with someone you can be confident is able to learn whatever else your company might need in the future, and writes better code by way of having a focus on programming knowledge, not language knowledge.