Some SPLATS, can be used as a spline, or have identical spline materials which work better. You can use the colorize -> alpha to paint transparency at certain spots along the spline, such as the edge's. By default, the spline will have gradient 0%-100% alpha at the ends, for blending.
That will most likely be the best solution for your question.
-
#Steam AliasWL%Streak
- 1.968562.633+23
- 2.555227.710+11
- 3.29446.865-1
- 4.275110.714+13
- 5.259143.644+3
- 6.250150.625+11
- 7.22491.711+11
- 8.19265.747+5
- 9.671423.613+7
- 10.5611.836+3