Shipping cost thresholds by product

Hello,

I need to configure different shipping cost thresholds depending on the products being bought.

I have a base table of shipping costs per weight. The prices are then adjusted based on purchase volume, and on the type of product bought.

For example, a customer ordering 20kg of an expensive product gets a 75% discount off the normal shipping rate, but if they order 20kg of a cheaper product, they only get a 50% discount on shipping.

I tried to do this with this plugin, but I have not been successful.

Is this possible at all with the free version of this plugin?