It is possible, but:
Depending on the combat system you are using it could involve a combination of scripting and eventing. If your using anything similar to the default battle system, in the sense that you formally enter the battle mode, you will need to script how those attributes are used to calculate hit and damage. You would also need to tweak the menu system to show your new stats, as well as develop either through events or scripting the way that those stats increase through leveling up. Use the search feature on the script forum to see what has already been developed in these regards. No need to reinvent the wheel.