If the types with the same name exist in both namespaces, you have a couple of options:
1) If the number of types is small, create an alias for that type:
using BorderStyle3d = tool.3dChartLib.BorderStyle;
2) If the number of types is large, you can create an alias for the namespace:
using t3d = tool.3dChartLib;
Then in your code...
t3d.BorderStyle
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