It’s not possible to loop backwards using the for each loop syntax.
As an alternative you can use a For i = a To 1 Step -1 loop:
Sub reverseForEach()
Dim i As Long, rng As Range
Set rng = ActiveSheet.Range("A1:B2")
For i = rng.Cells.Count To 1 Step -1
Debug.Print rng.item(i).Address
' Or shorthand rng(i) as the Item property
' is the default property for the Range object.
' Prints: $B$2, $A$2, $B$1, $A$1
Next i
End Sub
This works with all collections that have the Item property. For instance Worksheets, Areas or Shapes.
Note: The order of the loop when using on the Range object is from right to left, then up.