What will probably happen is the laws will ban all CGI porn, regardless of perceived ages.
OR
All will be legalized.
There is no middle ground................
This is what I expect will happen (or be attempted). Politicians who have no understanding of the technology will pass knee-jerk laws in response to issues they falsely perceive to be crises. "To save the children we must ensure that only authentic 18-year old teen girls are exploited in porn!"