How to make CR legend with color and different shapes using c#?

Hi, sap experts

I'm using push mode to design a rpt file, while the chart should be color.

But cr set the series shapes same as default, but with different color.

Now I want different color and differnet series shapes, Just as the below pic shows.

Pay attention to that push mode, there may be many(10 or 20 or more), so the legend shapes should be also differnet.

How to do it, thanks！