You can change fields in the configuration and transfer them to the sales order using structure VCSD_UPDATE. Solution
You can use user exits EXIT_SAPLCEI0_001 and EXIT_SAPFV45S_002 to insert new fields from table VBAP into structure VCSD_UPDATE.
User exit EXIT_SAPLCEI0_001 is used to document the author information of the set characteristic value in order to prevent the value assignment from user inputs in the sales order.
However, the author information is missing in the interface of the user exit. The function of the user exit is not included in the documentation of the function module either.
https://service.sap.com/sap/support/notes/644574 (SAP Service marketplace login required)
Key words :    , sales order, author information, characteristic value, function module,