The converted entity will be a spline. I use this technique for bringing in NACA data on airfoils.
Turn on curvature combs for anything that you use curve through xyz points. It is disappointing to find serious wiggles for a smooth shape like an airfoil. Simplify and smooth spline will not make it better. Best hope is to do a spline with eyeball fit and 4 or 5 knots each for top and bottom curves. Adjust with curvature combs showing.