UE 4.21 Simplygon LOD Edge Silhouette Preservation

I went back to 4.21 in order to try out this feature that got deprecated: Simplygon LODs | Unreal Engine Documentation

I tried it on a plane with some triangle density, hoping to conserve my plane silhouette and reduce triangles in it, not around it
But it resulted in chopping off the edges and not conserving them.

Is this the result I will get with the (now standalone) Simplygon?

expected result: