Hello @webmaster.mid Thanks for getting in touch with us.
Please note, WCMp is now rebranded as MultiVendorX.
By default flow of MultiVendorX, when a vendor is added to the site, we automatically generate a default shipping class for that vendor.
Now this shipping class is assigned to their products automatically. However, if desired, the administrator has the option to create multiple shipping classes, and vendors can then access and utilize them from their end.
For this modification kindly follow our doc here https://multivendorx.com/docs/code-snippet/remove-vendors-automated-shipping-class/.
If you need any further assistance from our end please let us know.