Hi hi. Firstly to report bugs or asking for help, please visit Discord: https://discord.gg/YKPscqHV8b
To quickly switch to available weapon in inventory, simple add a conditional branch Input.isTriggered('your button') then under it call command from Action Combat: Equip Next Weapon, done.
To make sword slash, there are 2 ways but I don't know which want you want yet so visit the Discord and tell me there :D