What I expected to happen was...:
I was shearing sheep and killing them with an axe, I had my shears in my offhand, and my axe selected in my hotbar.  I tried to kill the sheep immediately after shearing it and I got a weak attack even though the animation wasn't played.  I have to wait for the damage cooldown.

What actually happened was...:

Steps to Reproduce:
1. Put shears in your offhand
2. Select your axe. (Any kind? I was using iron)
3. Shear the sheep

4. Try to kill the sheep immediately after shearing it.