I didn't realize that you wanted this in your loop.

But this won't do much.  It just assigns the .top to the .top (no change at
all).  And even worse, it's refering to the original picture.

     With myPict
       .Top = .Top
       .Left = .Left
       'myNewPict.Top = .Top
       'myNewPict.Left = .Left
     End With

Untested, but it did compile:

Option Explicit
Sub Generate()

   Dim myCell As Range
   Dim myRng As Range
   Dim RngToCopy As Range
   Dim DestCell As Range
   Dim myPict As Picture
   Dim myNewPict As Picture
   
   Set DestCell = Worksheets.Add.Range("B2")
   
   With Worksheets("r")
       Set myRng = .Range("a2", .Cells(.Rows.Count, "A").End(xlUp))
   End With
   
   With Worksheets("Z")
   
       'this never changes, so don't do it in the loop
       Set myPict = .Pictures("Picture 3")
       
       For Each myCell In myRng.Cells
       
           .Range("H3").Value = myCell.Value
           
           Set RngToCopy = .Range("Branch")
           RngToCopy.Copy
   
           DestCell.PasteSpecial Paste:=xlPasteValues
           DestCell.PasteSpecial Paste:=xlPasteFormats
           DestCell.PasteSpecial Paste:=xlPasteColumnWidths

           myPict.Copy
           DestCell.Parent.Paste
           
           '"grab" the newest picture that was pasted
           With DestCell.Parent
               Set myNewPict = .Pictures(.Pictures.Count)
           End With
           
           'on the first loop, m6 is 4 rows and 11 columns from B2
           'should be the same relationship for the rest
           With myNewPict
               .Top = DestCell.Offset(4, 11).Top
               .Left = DestCell.Offset(4, 11).Left
               'give it a unique name
               .Name = "Pict_" & DestCell.Offset(4, 11).Address(0, 0)
           End With
           
           'get ready for next time
           Set DestCell = DestCell.Offset(10, 0)
       Next myCell
   End With

End Sub