Hi Fuzail,
Pls. go through below thread for similar requirement.
Copy Pricing COnditions from Shipment Cost do to Purchase Order
Also go through below KBA relevant to transferring shipment costs:
506605 - Info: PO generation when transferring shipment costs
Also go through below Badi's:
BADI_SCD_ACCTG Call During Shipment Cost Account Assignment
BADI_SCD_CREATE When Generating a Shipment Costs Document
BADI_SCD_CREATE_CHCK For Checks When Creating a Shipment Costs Document
BADI_SCD_PO_SELECT Call for the Purchase Order Item Determination
BADI_SCD_PROCESS_CHK For Checks During Shipment Costs Processing
BADI_SCD_SAVE When Saving Shipment Costs Documents
BADI_SCD_TRANSFER For Transferring Shipment Cost Items
I am not sure whether above Badi's will resolve your issue but hope it might help.
Regards,
Krish