I would rule the clockworks with my ASI max winmillion if this existed. It's literally the only thing that makes my Glacius more powerful offensively. By that I mean that if I had a larger attacking time window I could have way more fun and still kill monsters about as efficiently as with my Glacius. On a side note, the discs and speed make flinching a given in a way. By the way, did you know that winmillion is one of the best anti-mecha knight weapons? Discs activate shield, shield goes down and mecha knight goes down.
Winmillion doesn't make monsters flinch because it doesn't deal enough damage. The only way to make it interrupt monster attacks is to increase it's damage, which won't happen on a 4* weapon.