Most 3D printers don't shape very consistently, and don't use hard enough materials.
All the figure skaters I know use
two blades.
Another way to think of the rocker segments having the same tangent: Picture two circles, one completely circle inside the other, except at one point, which they share. An arc of the larger circle is the main rocker segment, and the smaller circle is the spin rocker, meeting at the point the circles share.
Maybe a professional grade jig saw would work well - if you use or make a circle cutting jig and clamp while you change radii. And a strip cutting jig for the toepick. Most good jig sa ws let you adjust the cut angle so you could make cross-picks, if desired.
If you have the money or shop access, a CNC cutter might do it too.
Do you have the skills to harden the edge after it is cut? Or if you start with hardened steel (so you need a laser cutter), to temper the rest of the blade so it doesn't shatter?
Appropriate alloy smooth uniform thickness sheet steel that is soft enough to cut, is expensive, for your first few failures, and is only available in a few thickness, which might not be right. Maybe a CNC cutter could effectively mill the blade near the edge to the right thickness.
If you don't use a stainless steel like 440C, you will probably need to plate the metal with nickel (nickel/chromium if you want it shiny like MK & JW), to slow rust.
Even if you measure just one blade, you have to figure out how blade shape varies with blade length. If the whole blade scale, the radii would scale too. (I don't understand why that isn't done.) Perhaps the fraction along the length of the blade where the blade radii changes stays the same?? And perhaps the relative position of the "touch point", where a straight edge can touch both the back toepick and the curved section of the blade, stays the same??
Since MK/JW blades aren't cut consistently, you might need to measure many blades of each size.
Maybe there are good reasons why only a few companies dominate the high end figure skate blade market. The ideas are easy, but not getting everything right. I apologize for wasting your time with a dumb idea.