I was just discussing in general, but if you can only comment on immigration-related ones I’d be curious to hear what some common issues are that startups run into when hiring immigrants.
They're really no different from other companies hiring foreign nationals. Sometimes, however, with startups, USCIS wants to make sure that it's a real business and will ask for evidence of this in the form of client contracts or letters of interest, funding, products or product development, etc.