selling unofficially licensed models of real products

The only valid answer is the one given by the law. If you don't want trouble, don't sell anything you don't own or have written permission to do so. The fact that some companies are tolerant does not mean that they cannot exercise their rights at any time

This question is much harder to answer than you think as regulations are different from region to region, from country to country and the companies in question themselves have different views on it.

Here on CGT the EU regulations are to follow.

You can get opinions on this forum, but if you want "official" answer, you have to address the question to CGT:
support@cgtrader.com