Hello Rohit Raisinghani,
The described scenario is not possible, because when dragging a stacked area item in blend, it generally allows you to customize the template (shapes, masks, etc) for all stacked series. Appearance customization can be done in this way only for the first series.
We recommend you to use the PaletteBrushes approach
described in our help if you want to define custom colors for your series.
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