Civil War Swords were important to officers.
It was the greatest symbol of their authority. It was a very useful tool to direct men in battle.
You could say it’s somewhat like how a conductor uses their wand to lead an orchestra.
Beyond a symbol of leadership however swords did not really have any function in combat.
Stonewall Jackson’s sword actually rusted because it was hardly ever removed from it’s scabbard. He just didn’t use it.
Swords just like the bayonet could be intimidating and did see some combat, but with gunpowder weapons in great abundance it just didn’t have a big place on the Civil War battlefield.
What about the Saber? Sure this curved sword was still being used by the cavalry, but the hay day of the cavalryman wielding his saber in combat was pretty much gone by the time the Civil War began.
Wielding a saber was mostly done for show rather than for combat purposes.
With multiple shot pistols and carbine rifles it became extremely dangerous and nearly impossible for cavalry to get close enough to the enemy to actually engage in any kind of a sword fight.