LegendKey.MarkerBackgroundColorIndex (Excel)

Returns or sets the marker background color as an index into the current color palette, or as one of the following XlColorIndex constants: xlColorIndexAutomatic or xlColorIndexNone. Applies only to line, scatter, and radar charts. Possible return values are xlColorIndexAutomatic - Automatic color, xlColorIndexNone - No color.

ActiveChart.Legend.LegendEntries(1).LegendKey.MarkerBackgroundColorIndex = xlColorIndexAutomatic