re,
voici la modification,
Sub Transfert()
For Each f In Worksheets
If f.Name <> "Données" Then
Set sh = Sheets(f.Name)
rw = sh.Cells(Rows.Count, "A").End(xlUp).Row
col = sh.Cells(3, Columns.Count).End(xlToLeft).Column
For i = 4 To rw
For j = 2 To col
If sh.Cells(i, j) <> "" Then
rw0 = Sheets("Données").Cells(Rows.Count, "A").End(xlUp).Row + 1
t = sh.Cells(i, 1) & " " & Format(sh.Cells(3, j), "dd/mm/yyyy") & " " & sh.Cells(i, j)
If IsError(Application.Match(t, Sheets("Données").Range("A:A"), 0)) Then
Sheets("Données").Cells(rw0, "A") = t
End If
End If
Next j
Next i
End If
Next f
End Sub