Dim wsh As Worksheet, dl As DataLabel, series As series
  Set wsh = ThisWorkbook.Worksheets(1)
  Set series = wsh.ChartObjects(1).Chart.SeriesCollection(1)
  For Each dl In series.DataLabels
    'TODO: задать координаты по своему алгоритму
    dl.Left = 50
    dl.Top = 50
    Exit For
  Next dl