You will have absolutely have a really hard time finding a job teaching English. Doesn't matter if you are born overseas, or if you don't know any Chinese, or if you are adopted. There is this disconnect of seeing an asian face and English teacher. Doesn't matter if you have a Harvard PhD in English lit., they will always prefer a white (or to a lesser extent black) face teaching their kids over you because it will look more authentic.

Even if you can get a english school to overlook this, when the kids and parents show up they will complain.

When you get your proper credentials, You might have a better chance at a properly accredited international school where the student are international, not locals.