Function to get unique sorted words

Use this UDF like:

=get_unique_sorted(A2)

Option Explicit

Dim UniqueItms As New Collection

Function get_unique_sorted(s As String)
  Dim i As Long, j As Long, k As Long, m As Long, nWords As Long, lenMax As Long
  Dim w As Variant, arr As Variant, b As Variant, c As Variant, t As Variant
  Dim s1 As String
  
  arr = Split(s, " ")
  nWords = UBound(arr) + 1
  For Each w In arr
    If Len(w) > lenMax Then lenMax = Len(w)
  Next
  ReDim b(1 To lenMax, 1 To nWords)
  ReDim c(1 To lenMax * nWords, 1 To 1)
  
  s = Left(s, Len(s))
  For Each w In Split(s, " ")
    i = Len(w)
    For j = 1 To UBound(b, 2)
      If b(i, j) = "" Then
        b(i, j) = w
        Exit For
      End If
    Next
  Next
  
  m = 1
  For i = UBound(b, 1) To 1 Step -1
    Set UniqueItms = Nothing
    For j = 1 To UBound(b, 2)
      If b(i, j) = "" Then Exit For
      Call AddWord(b(i, j))
    Next
    
    For Each t In UniqueItms
      c(m, 1) = t
      m = m + 1
    Next
  Next
  get_unique_sorted = Join(Application.Transpose(c), " ")
End Function

Sub AddWord(itm)
  Dim x As Long
  For x = 1 To UniqueItms.Count
    Select Case StrComp(UniqueItms(x), itm, vbTextCompare)
      Case 0: Exit Sub
      Case 1: UniqueItms.Add itm, Before:=x: Exit Sub
    End Select
  Next
  UniqueItms.Add itm
End Sub