Sort parent nodes XML depends on child nodes values

Question

I have a following XML

Answer 1

This transformation implements exactly the stated requirements. It takes special care to preserve the exact order of the elements that are not to be sorted. No other answer at present does this:

When applied on the following XML document (the same as the provided one, but with an additional inserted between Data1 and Data2 so that we can verify the preservation of ordering of the non-sorted elements):

    
    
    
        
        
            2222
            field1
        
        
            ABC
            field2
        
    
        
    
        
        
            1111
            field1
        
        
            XYZ
            field2
        
    

produces the wanted, correct result -- note that the position of is preserved:

   
   
   
      
      
         1111
         field1
      
      
         XYZ
         field2
      
   
   
   
      
      
         2222
         field1
      
      
         ABC
         field2