Some companies offer 3D models you can dress up. There was also a startup in Germany if I remember correctly that offered the technology for online retailers. I didn't see it used much though.

We had another fashion related project about 5 years ago, offering custom made hoodies and jackets online. In the end we gave up because many of our customers didn't get the sizing right even though we had detailed tutorials for that, forms with illustrations that showed what to measure and so on.

If you spend 150 bucks on a jacket and the sizing is wrong... well that's no fun. Its not such a big deal for shirts.