A week ago i tried to do it for knife, and it seemed working. We only need to create a code to imitate the stabbing/slashing. I'm kinda sure about that we could do the same with other weapons if we could imitate their actions either.
In this code i blocked all the default actions and tried to work with client_prethink and get_user_button(), the animations worked correctly, didn't have time for the stabbing/slashing..