Stock transfer between plants in a company with different price
As I said in my reply above you cannot have a different price and make a profit or loss on the material.
Freight costs are different because these are normal accounting postings that can occur when you transfer stock around within your company. BUt you cannot have a Bill and a profit (or loss) unless the movement is going between plants that belong to separate company codes.
If you are doing this or have seen it done then it will be due to a large, complex and risky modification and I strongly recommend that this is not something bthat should be done without the full knowledge and acceptance of the accounting that results (from your auditors).