You can adjust the shipping rates for Woocomerce like this.
Login to wordpress.
Woocomerce > settings > shipping > Add shipping zone.
Add Europe for example, shipping methods > flat rate.
And here we can edit.
Method title can be DHL Europe for example (it’s just a text that the user will see).
Tax status none.
Cost, we need to write some mathematic code.
Something like this.
Shipping cost per item/product plus extra for more products
8 + (4 * [qty] – 4).
This means the shipping cost is:
8$ (4$ * [quantity] – 4$).
If the user will buy one item, the shipping cost will be 8$.
If he buys 2 items, the cost will be 8 + 4 = 12$
If he buys 4 items, the cost will be 8 + 4 + 4 + 4 = 20$.
So for each one more item, he will pay the extra 4$.
Normal Shipping cost per item
8 * [qty]
This is the code, 8$ * quantity. If the user buys 2 items, it will be 8 * 2 which is 16$.
If you have questions, let me know in the comments.