How to standardize dates

Good Morning
I need to make a macro to fix all the Date entries that are entered. Some dates are entered with 10/01/2021" others "01-10-2021" or "01.10.2021".
With this routine, when opening the file, all dates are reset to the slashes "/".
The routine works but is quite slow. Is there another way of faster programming to do?

Thank you for your help

Sub Formatar_Datas()
    Application.Calculation = xlCalculationManual
    Application.DisplayAlerts = False
    Application.ScreenUpdating = False
    Application.EnableEvents = False

    Dim Cell As Range
    Dim Cont As Long
    Dim ContBD As Integer
    
    Dim Arr1 As Variant
    Arr1 = Array("J4:J", "Q4:Q", "R4:R", "S4:S", "T4:T", "U4:U", "V4:V", "W4:W", "X4:X", "Y4:Y", "Z4:Z", "AA4:AA", "AG4:AG", "AI4:AI", "AK4:AK", "AT4:AT", "AV4:AV", "AW4:AW", "AZ4:AZ", "BB4:BB", "BD4:BD", "BM4:BM", "BO4:BO")

    ContBD = 1
    For Cont = LBound(Arr1) To UBound(Arr1)
        For Each Cell In Folha3.Range(Arr1(Cont) & Folha3.Cells(Folha3.Rows.Count, "C").End(xlUp).Row)
            If IsDate(Cell.Value) = False Then Cell.Value = ""
            If Len(Cell.Value) = 10 Then
                Cell.Value = Replace(Cell.Value, ".", "/")
                Cell.Value = Replace(Cell.Value, "-", "/")
                Cell.Value = Replace(Cell.Value, "_", "/")
            End If
        Next Cell
        ContBD = ContBD + 1
    Next Cont

    Application.DisplayAlerts = True
    Application.ScreenUpdating = True
    Application.EnableEvents = True
End Sub