XL 2019 Renommer en masse les titres de colonne des .CSV

Function replaceAllCsvHeader(Dossier)
    Dim FsO As Object, fich, x&, subdossier, contenu As String

    Set FsO = CreateObject("Scripting.FileSystemObject")
    Set Dossier = FsO.GetFolder(Dossier)
    For Each fich In Dossier.Files

        If LCase(Right(fich, 4)) = ".csv" Then
            'lecture
            With CreateObject("ADODB.Stream")
                .Charset = "utf-8": .Open: .LoadFromFile (fich): contenu = .ReadText()
            End With

            'ecriture
            With CreateObject("ADODB.Stream")
                .Type = 2: .Charset = "utf-8": .Open: .WriteText Replace(contenu, oldChaine, NewChaine)
                .SaveToFile fich, 2
            End With
        End If
    Next
    For Each subdossier In Dossier.subfolders
        replaceAllCsvHeader subdossier.Path
    Next subdossier
    Set FsO = Nothing

End Function