There's a basic common misunderstanding that there's a connection between an individual's underlying nonimmigrant status and his or her green card options. There's no connection. Underlying status has no bearing on green card options. The connection is merely coincidental. Green card options are analyzed separately regardless of underlying status. Underlying status can impact timing and travel but not the path. So, as an E-2 you can pursue a green card and the path will depend on your job, your qualifications, etc.