3 is a little more complicated than 2 was, but the principles are the same

Dim strName As String
Dim strNewName As String: strNewName = ""
Dim strPath As String
Dim strExt As String
Dim strDate As String
Dim vNewDate As Variant
    strPath = "C:\Path\"
    strName = "Report_2017-09-05-05-46-13.xlsx"
    If InStr(1, strName, "_") > 0 Then
        If UBound(Split(strName, "-")) = 5 Then
            strExt = Right(strName, Len(strName) - InStrRev(strName, Chr(46)) + 1)
            strNewName = Left(strName, Len(strName) - Len(strExt) - 2)
            strDate = Split(strNewName, "_")(1)
            vNewDate = Split(strDate, "-")
            strNewName = Split(strNewName, "_")(0) & "_" & _
                         vNewDate(0) & "-" & vNewDate(1) & "-" & _
                         vNewDate(2) & strExt
            MsgBox strNewName
            'Name strPath & strName As strPath & strNewName
        End If
    End If