WooComemrce and other on-line e-commerce systems typically present upsell and cross sell items as follows:

Upsells - These are products you wish to suggest to the customer that they might purchase instead of what they are currently looking at (i.e. spend more, better quality, better margin)

Cross-sells - think of as  "Do you want fries with that" i.e. They have a hammer in their shopping cart - suggest a nailbag, nails, a hammer holster or even electric saw!