Why a fixed amount
The subsidy should not grow with the value of the goods. Gross and net are linked through the tax rate: €10.00 gross is €8.40 net at 19% tax.
The shop pays €10.00 of the shipping costs for deliveries to Austria. The plugin adds a fixed discount to the cart for that as soon as the delivery country matches.
On the left the rule in the Rule Builder, on the right the item's fields that matter. Everything else stays as it is when you create the item.
RuleRule Builder
Shipping subsidy −€10.00
The discount is a line of its own in the cart. Shopware calculates the shipping costs themselves as always; the subsidy sits next to them. It stays at €10.00 with 2 or 3 products too, as measured in the demo shop.
Cart2 items
Subtotal€485.95
The subsidy should not grow with the value of the goods. Gross and net are linked through the tax rate: €10.00 gross is €8.40 net at 19% tax.
The customer sees that the shop pays for something, instead of the shipping costs quietly dropping. The shipping method's price matrix stays as it is.
For Switzerland with a different amount, create a second item with its own rule. Every item has exactly one rule and one amount.
What to watch out for: If the subsidy should only apply above a certain goods value, use the condition "Subtotal of goods (excl. discounts/fees)". The "Cart total (incl. shipping)" also counts shipping and the plugin's items, so with surcharges the rule can switch itself off again.
If product A, B or C is in the cart, the delivery goes to Austria or Switzerland and the customer is a retailer.
For deliveries to certain countries the shop pays part of the shipping costs.
A discount for payment in advance, a fee for cash on delivery: one item per payment method.
A surcharge per bulky product when delivery is by freight.
A real product from the catalogue that retailers get once, with their first order.
Once the goods total reaches €50.00, a catalogue product is added free of charge.
A magazine or a sample that the customer can see and remove.
In Advent, one gift wrap per product in the cart, which the customer can remove.