Is it legal to sell models that do not exist?

It looks like each of the models I've looked at with this particular profile, actually does have 6 STLs uploaded for each advertisement, so I don't see a problem there.
Though I've never tried, but I don't think it's possible to create an item for sale here without uploading anything. Most likely, the text was from an Etsy sales site where they just copy and pasted the details of the item. I believe that on Etsy, that files aren't held on site and sellers must email the files to the customer.

There are problems.

For example:
Source: https://www.flaticon.com/free-icon/sport_4229254
https://www.cgtrader.com/3d-models/household/other/stamper-051-sport-1

Of course, it's possible that this seller has an exclusive agreement with Freepik Company but I think not and there is direct violation of the license condition.

In addition, all of this user's items are uploaded in wrong categories.

This profile will be investigated later, since there is a lot of work besides it (217 spam-accounts and many more links with violations).

Profile https://www.cgtrader.com/printerestmodels banned.