Hello,
I have struggled with the same problem and cannot find an answer. The order short text (COAS-KTEXT) seems to be language independent. If you change it, it changes in all logon languages. This is awkward, when same investment orders are reported in two countries.
For all the other CO Master data (cost centers, cost elements) the text can be maintained in logon language.
Hope some one knows a solution.
BR Ritva