In my experience, because of the competition for talent, startups often are more open to employing foreign nationals than many large, established companies. The terms EB-1, EB-2, etc. refer to green card categories and the green card process takes a while so that's probably not the initial path toward working in the U.S. The likely visa options will be the L-1 (as a transferee) or an O-1 and oftentimes founding engineers or early stage employees qualify for the O-1 or can take steps to qualify. Both the L-1 and O-1 require company sponsorship.