I make all my bows using ALMOST exclusively my KaBar knife. I fire up the elt sander only to true up edges, shape handles and remove tool marks.
I have cut osage with just my knife and start to finish made many just the one tool. Yes it is metal but with osage stone would work just as well. See, except for felling the tree, there is very little actual chopping chips out the wood. You are working up large sections to split off the stave for stock removal. Osage splits so well it takes less effort to male a stone age osage bow than it takes to make any white wood bow. This I know for a fact. I have used a small baseball bat to split stave once i got the split started. No edge needed.
. Also, who says tje edges of stone tools were serrated? They would not have done that to those tools. Rather, they would have just spalled off a good flake and used its sharp broken glass like edge to scrape away the wood.
Eddie, I would love to see your stone ax.