After making a product Free Shipping it seems that this overwrites the shipping settings for all remaining products have. So everything that is in the basket will be free shipping. Why is that? We only need the one item with free shipping not all from basket.
The solution mentioned in the link has flaws with free-at-carts, mixed carts and blocked categories
You’ll need a third shippingmethod that capture when the all others are not working.
standard
free
others (freeshipping is recognized but calculated anyway) [EDIT: and „Ausweich Versandart“]