I am curious about the portrayal of children and women in the movie Free State of Jones - how accurate it is? No doubt they had an impact, but I am not sure they took part in real battles and fight against the Confederacy armies. Their actions as feeding, hiding and sheltering deserters in swamps is quite true, but taking part in a combat, reloading cannons and shooting rifle seems to me just heroic overstatement. At moment a little search did not brought me closer to viable source the way film portrays women and children among the revolt - to me it seems simply an exaggeration?
I don't know anything about the specific case of Jones County.
As for loading cannons, I don't see much difference except in the amount of labor between loading cannons and loading rifles. In the days before breech loading rifles and repeaters it was common for non combatants to load muzzle-loading muskets and hand them to shooters, instead of having the shooters waste time loading.
For example, I once read about a family attacked by Comanches in Texas about 1840. A 12 year old boy shot the muskets while his parents and siblings loaded them for him.
Loading a cannon would be harder work, but I guess many women would be as strong as John Cook, a bugler in the 4th US Artillery. At the battle of Antietam he was fifteen years old and about five feet tall and weighed about 100 pounds. He did the work of several men loading and firing a cannon by himself until General Gibbon came along and did part of the work.
19th Century American society believed that combat was men's work. The only legal enlistments in armies, for example, were those of men - and boys if musicians. It is currently believed that a few hundred women disguised themselves as men and enlisted in the Civil War.
It seems to me that it would take unusual circumstances for more than a few Jones County women and children to fight the Rebels. Unless there was some special circumstance in the Jones County situation women and children should have been only a very small part of the Jones County fighters.