I just throw punish all the follow ups, except for the P follow up where I just mid punch hold instead. That move is really slow that I can react to it. Besides, the WR4K is not delayable.
I am not really referring to the K follow up, but just the first WR4K. The follow ups or free cancelling can be punished easily except for the P follow up, which I can easily score a counter or high counter hold every fucking time.
Like I said, you do not need to worry about the command flipping around. Both the second part and third part of the Izuna can be done in any direction you want.