With the CSV import tool included in Store Commander, you can create and modify products in bulk when working in Multistore mode.
Using the CSV import in Multistore more requires 2 specific fields (in your CSV file):
id_shop_default: sets the default store for products - mandatory when creating products
id_shop_list: stores where products will be present (creation) and where modification will be applied (modification) - mandatory in ALL imports
If you do not specify id_shop_default, the import will work but there will be missing links in your database.
If you do not specify id_shop_list, you will most probably get an error 'price_is_empty', reported in this article.