Prevent registration by users with the same first and last name

[uniqbuy]

In VM1 I used this hack to stop registrations from people using the same first and last name: https://forum.virtuemart.net/index.php?topic=52137.30

Is there something similar for VM2. I do not want to use Keycaptcha on the registration form as I run an ecommerce shop and think this will put people off. (if there is a very simple multiplication captcha or similar that would be fine)

Any help would be great.

Thanks