I think all regulatory regimes that have any chance of addressing this would require government support. Perhaps something like requiring any model to first go alone to identify herself to the police or other authority and certify her age. This would provide an opportunity to escape a captor. Perhaps this would be an annual thing.
But the proper incentives would need to be in place. She'd need to be allowed to stay in country if she is a foreign victim of trafficking, for example. We would want to prevent this from becoming some type of guild where incumbents can keep out new competition. And the police would need to be supportive in this process (i.e. promptly inform OF of models' eligibility, and otherwise participate in the process in good faith). It's hard to see that happening in, e.g., the United States.
But the proper incentives would need to be in place. She'd need to be allowed to stay in country if she is a foreign victim of trafficking, for example. We would want to prevent this from becoming some type of guild where incumbents can keep out new competition. And the police would need to be supportive in this process (i.e. promptly inform OF of models' eligibility, and otherwise participate in the process in good faith). It's hard to see that happening in, e.g., the United States.