Alike the 'B-Decimal Transform . to ,' - the date format may also vary corresponding to different SAP environments. if the date format in SAP is (DD.MM.YYYY) as shown in the image below.
And on contrary if the date format in excel is (MM/DD/YYYY) as shown in the image below.
In Mapper tab, assign 'D-Transform Excel date to DD.MM.YYYY' DF for the corresponding field.
Following image represents how Process Runner adapts the transformation on-the-go.