You can extend E2, but you cannot apply for GC for E2, since E2 is not a dual intent visa. It's like a TN1 except that it's for entrepreneurs, and available for a much broader amount of countries.
The catch is that you must OWN at least 50% of the company you're working on. So for example if you plan to work in say Microsoft or Facebook, you must own at least 50% of Microsoft or Facebook.
- Be seeking to enter the United States solely to develop and direct the investment enterprise. This is established by showing at least 50% ownership of the enterprise or possession of operational control through a managerial position or other corporate device
https://www.uscis.gov/working-in-the-united-states/temporary-workers/e-2-treaty-investors
You also cannot work in any other company except the company you're currently invested on. In the event, that the said company is sold or folds, you get kicked out of the US, similarly if you leave the company either by resignation or retirement, the US gets to kick you out.
Alternatively you can also work for a company whose original ownership is in your country provided that you own 50% of that company in your country. For example, you opened ABC restaurant with a 50% stake in your home country. The restaurant then decided to open a separate international brand XYZ restaurant in the US. The XYZ is owned exclusively by ABC, hence from the US perspective you are NOT the owner of XYZ restaurant. But since you own at least 50% of the parent company ABC, you would be eligible to work for XYZ company in the US.
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That said, I feel that it's too risky, too capital intensive, and personally I'm just an engineer, without an interest in entrepreneurship, so I would have to give this one a pass, but then again if it's your cup of tea. More power to you!
