The shipping functionality is being handled by WooCommerce. So you can use any WooCommerce compatible shipping for your site. WooCommerce already has some built-in shipping methods, these can only be configured by the admin and will work for each vendor. The vendors will not be able to configure any shipping charges of any shipping method added by the admin. To know more about how to configure WooCommerce shipping please read their official documentation.
The vendor can only edit the shipping cost if the admin has added the “Vendor Shipping” method. To know more on how the vendor can configure the shipping cost, please do refer to this doc : https://wc-marketplace.com/knowledgebase/wcmp-shipping/
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