Woocommerce needs a proper pick-list (multi-order). This is industry-standard.
I've worked in a few warehouses in my time: and every multi-order pick-list i have used since, is sorted like this:
- product type / zone
- product (then the order numbers that need that specific product has its number listed against that product, with the quantity of that product)
Its so simple! only walk to each product stocking bay ONCE, not per order!
And then once the products are placed in the assembly area, we use pack-lists. This is not rocket-science - its been around decades! Woocommerce should and could offer this too.
Version 3.3.0 has put this feature in YAY!