For shipping to countries outside the EU, such as Switzerland, customs documents are required. When shipping with DHL and the Österreichische Post, you have the option to automatically generate the export documents when creating a shipping label. For all other shipping carriers, the export documents must be filled out manually. You can find further information e.g. here or here.
Note on Deutsche Post: For the Warenpost International product, the additional information mentioned here must also be maintained. Unlike the other shipping adapters, however, no additional export document is required, as this function is handled by the Deutsche Post label that is created.
Automatically generating export documents
To activate this setting, open the shipping cost management (Shipping Costs) under Settings → Shipping Costs, open the relevant shipping method, and navigate in the lower area to the tab of the shipping carrier (DHL or Österreichische Post). There you will find the option Create export documents, which causes customs documents to be created in addition to the shipping label. Now switch to the Country selection tab and drag the relevant countries from the list of available countries to the list of selected countries on the right, or use the arrow icons.
If the creation of export documents is enabled for an order, the individual line items of the order are transferred directly into this document. For DHL, the number of line items on the export document is limited to 99; for the Österreichische Post, the number of line items on the document is unlimited. If an order shipped with DHL has more than 99 line items, these are combined into a dummy line item that corresponds to the accumulated value of all remaining line items. This is necessary so that the order value shown on the export document matches the invoice amount.
Item weight
Since not only the prices of the line items are recorded on the export document, but also their weight, the weight used for the shipping label is also adjusted to match the total weight stated on the export document. This means that the packaging material is disregarded in this case.
Customs tariff number and country of origin
Please note that for the export documents, the fields Customs tariff number and Country of origin must be maintained in the product details, as this information is required on the export documents. You can find these fields in the product master data in the Custom fields section. You can look up the relevant customs tariff numbers, for example, here.

