If you're just looking to reduce weight, then your only real option is to take wood off by sanding or further shaping. You can remove stickers, scuff sheet and toe guard if it has these, which would remove maybe an oz, but it's minimal and leaves you without protection against moisture and nice stickers 😆
If it's a question of it being unbalanced/bottom heavy, then you can add an extra grip or tape to the handle, which adds weight but often helps.
Or, you can just play with it and see how it goes. In my opinion and experience (unless it's arrived way over the weight requested), most people would get used to an oz or two more in a bat once they use it.