how can i make an axe that can disable a shield and behaves like a sword so you can hit multiple mobs at once

i want to make a mod with an viking axe that disables shields and swings like a sword and i dont know how to do that with multitool and i dont think there is another way besides multitool

can you please explain to me what i have to change in BattleAxe.java(the java file for the axe)