In embedded EWM/TM integration with ASR (planning type F), we are not able to cancel the outbound delivery.
Created OBD in LE and replicated to EWM/TM. When I try to delete the delivery in EWM getting an error "Document 8000000X created by SAP TM; Deletion not allowed".
If I try to make the delivery quantity to Zero in EWM delivery line item, it's getting saved and updating the LE delivery quantity to zero but updating corresponding FU.
If I understood correctly, this query is about cancellation of delivery which is already distributed in EWM so its Freight Unit in TM get deleted. Did you try zero PGI in EWM?
Check this blog if it helps: https://blogs.sap.com/2021/08/23/ewm-cancel-picking-cancel-outbound-process/