In the Magento 2 Admin a new column can be added to the Manage Products screen called "Last Import Date"
Note: If you do not see the "Last Import Date" column as one of the fields in your Manage Products screen you can see if it is available by clicking on the "Columns" button. If this field is not available please contact Commerce5 support.
Once added you will see this field in the column list. The "Last Import Date" value indicates the last time the particular SKU had been imported into Magento.
When you click on the column header for "Last Import Date" it will sort all the SKUs by this field.
Any SKU that has a blank value or a date that is prior to the current date is NOT currently part of the product import feed. It is recommended that these SKUs be addressed by either deleting or disabling them.
Note: It is highly recommended that you review the SKUs in question before deleting or disabling them.