As with the other Sales Layer connectors, links must be established between the fields included in the PIM forms and the target fields, in this case, Amazon fields.
There are various technical aspects that have an effect on the performance of your account on Sales Layer and the processes related with it, such as ecommerce synchronizations and content exportations.
Some popular MarketPlaces suggest an exchange based on a Parents/Child structuring that will allow a better arrangement of product information and variants in the final result.