My bad, I got myself confused with the columns and rows. I thought you wanted a blank column. My bad.... is this in QlikView or Qlik Sense? and do you know how many blank rows will you need in total or is this dynamic?
So, I was able to insert a blank row for each SalesOrderID, but I am unable to sort it in a way that it alternate... currently it just shows up at all SalesOrderID together and all empty rows together... this can be fixed if we can add SalesOrderID another time (may be at the end of the table), but this SalesOrderID will show the same number on both rows.... Is that something which can work for you?