Hi,
There are two ways to go about it with HikaShop's core features:
1. In the settings of your shipping methods, you can activate the "shipping price per product" setting. Once you do, when you edit a product in the backend, you'll have a new section called "shipping prices". There, you'll see each shipping methods with that setting activated, and for each one, you'll be able to either configure extra fees for when the product is in the cart, or use the "block" checkbox to remove the shipping method from the checkout when the product is in the cart.
So the restriction will be at the product level, not the category level, and you need to go through each product, so it can be cumbersome in some cases, but the benefit is that you have a more fine-grain control.
2. You could create warehouses in the menu System>Warehouses, restrict your shipping methods to warehouses, and use the "warehouse" setting of your products to link them to warehouses. That way, you'll be able to provide different shipping methods for different groups of products during the checkout.
While you also need to edit each product to select the warehouse, you can actually use mass actions to automatically set that link based on the category of the product. That way, it could potentially save a lot of time.
Also, while this method allows you to still offer the restricted shipping method for other products which are not concerned by the shipping limitation in the same cart with products from different warehouses, that might not be something you want to offer as it might lead to stacking of shipping fees (one shipping fee per warehouse).
Another option is to use this:
www.brainforge.co.uk/shop/downloads/prod...pping-extra-features
From what I can read there, it allows for category restriction. However, I've never used it or seen the code of the plugin. So I would recommend checking with the developer.