Mapping fields from Inbound Shipment to Item Receipt

By using the Standard features of NetSuite, we cannot map fields from Inbound Shipment to Item Receipt

• If we use workflow on Item Receipt, then the fields in the Inbound shipment won’t be listed even though there is a field named Inbound Shipment in IR.
• On using Sourcing and Filtering options for custom fields in IR, the fields in Inbound shipment won’t be listed.
• If we use CSV import to update IR fields after exporting the Inbound Shipment field values, then we can’t use it because IR does not support CSV import.
• The only method is deploying a script