Hello,
In this case you can set up stock transport orders between two plants in your system that allow stock movement.
The two plants involved in STO can belong to any company codes.
Please refer
Stock Transfer Using a Stock Transport Order - Managing Special Stocks (MM-IM) - SAP Library
Working with Intercompany Stock Transfer - Billing (SD-BIL) - SAP Library
SAP Note 543821 - FAQ: cross-company processing
543821 - FAQ: Cross-company processing
Best Regards,
R.Brahmankar