You can cheat. See attached, button and notes in the code.
Code:
Sub blah()
Sheets("Foglio1").Copy After:=Sheets(Sheets.Count) 'makes a copy of the sheet; remove when development finished.
With ActiveSheet.ChartObjects("Grafico 1").Chart
PlotTop = .PlotArea.Top
OrigTop = .Axes(xlCategory).Top
.Axes(xlCategory).MajorGridlines.Delete
.Axes(xlCategory).Delete
.PlotArea.Top = PlotTop - 10
.FullSeriesCollection(1).ApplyDataLabels
With .FullSeriesCollection(1).DataLabels
.ShowCategoryName = True
.ShowValue = False
.Position = xlLabelPositionBelow
End With
For Each pt In .FullSeriesCollection(1).DataLabels
pt.Top = OrigTop
Next pt
End With
End Sub