If your two groups of data are coming from different inputs, the most simple solution is to edit those by adding/removing a column before inputting to Alteryx.
If they are like that in the source, you will first need to split the two groups with a filter. I would use the expression !IsNull([F1]) and then edit the F output (the bottom section).
You should be able to use a dynamic rename tool. Make sure the rename mode is set to formula and all fields are selected. The formula should look something like this:
Replace([_CurrentField_],Right([_CurrentField_],LENGTH([_CurrentField_])-1),ToString(ToNumber(Right([_CurrentField_],LENGTH([_CurrentField_])-1))-1))
You can then use a select to deselect the F0 Field that will be created (this should be the blank column
From here you can union your two sections back together and they should be matched up.
Hope this helps
