"Energy swords" in history are known under the names - "f lambard, flammard, flammenschwert and flamberge". Flamberge (old-fashioned. Flamberge, from German. Flamme - flame, the French version of the Flamberge transcription is also found) - "flaming" blade.
During the Renaissance, "flaming" blades came in all sorts of sizes, from a tiny lady's stiletto, to truly gigantic Zweihander swords over 2 meters long.
Flamberg is a two-handed (less often - one-handed or one-and-a-half) sword with a wavy (flame-shaped) blade. It was used in Europe (especially in Switzerland and Germany) in the 15th-17th centuries.
And this man died from what? Here is an excerpt from the historical description of the outcome of the "battle": “There has never been a case when wars were fought in an enemy country with less damage to the attackers than in this one; for in such a great defeat and in a battle that lasted four hours, only one person died, and he did not from wounds inflicted by hostile weapons or any noble means, but, falling from a horse, was trampled to death ». Question: for more than four hours, more than 8000 soldiers were hacked with their swords and other weapons, and the only victim in this war died because he forgot that “safety is above all else”? It looks like there was something in Leonardo's painting that we shouldn't have seen.