From sap help, there is a section about 'Display Variant'.
Use:
You can select the information to be displayed in the field mapping
This function is particularly useful to experienced users who want to specifically modify the field mapping.
Features:
In the change mode of step Maintain field mapping and conversion rules, choose -> Display variant.
However, I can locate this functio when I go to Maintain field mapping and conversions rules. Can anyone tell where this function locates? Thanks for your help!