Hi..
Even if you have wrong standard cost, I don't think that it would be a serious problem if you use material ledger.
Because variance between actual and standard will be transferred into consumption and stock through material ledger closing.
If you change wrong standard cost, refer to below process.
You should pay special attention to delete standard cost. If not, you will meet inconsistence problem.
1.You check whether MM documents related to the material were occurred after you release wrong standard cost
If so, you should reverse MM documents to avoid inconsistence problem.
2.You delete std cost using t-code CKR1.
3.You re-calculate and mark STD cost.
4.If you use material ledger, before release std cost, you should change ML status into
“Period Opened” using the program supplied by Note 574930.
If you don’t use material ledger, you release std cost.
If you have the situation that you cannot reverse MM document, you should avoid deleting wrong standard cost.