Remplacer lettre par une lettre -EXCEL-

Public Function RemplacerBB(Modele As Range) As String  
Dim Chaine As String, i As Integer, L As Boolean  
Dim R As Integer, C As String, Tp As String  
    Application.Volatile  
    Chaine = "AZERTYUIOPQSDFGHJKLMWXCVBN"  
    For i = 1 To Len(Modele)  
        R = Asc(Mid(Modele, i, 1))  
        If R > 96 And R < 123 Then 'minuscule  
            L = True: R = R - 32  
        Else: L = False  
        End If  
        If R < 65 Or R > 90 Then 'espace  
            Tp = Tp & " "  
        Else  
            C = Mid(Chaine, R - 64, 1)  
            Tp = Tp & IIf(L, LCase(C), C)  
        End If  
    Next i  
    RemplacerBB = Tp  
End Function

=RemplacerBB(D4)