It still doesn't add up though. His chase is his only way of causing the "slow reflex" effect yet he gets multiple attacks 1: without landing his chase, 2: Gets multiple attacks even when attacking characters who were not hit with his chase.

And there is still nothing in his skill descriptions to explain how sometimes it also gives multiple standards to characters who do not attack characters with said debuff, like healers or shield units

The only way shisui in the english version makes any sense is

1: They changed his skills so that all of his attacks cause slow reflex, including causing it to characters hit by the splash damage from his attacks but didnt change the descriptions to say this.

2: They have changed how the sluggish/slow reflex debuff works but didnt bother to tell us this as there is no info or sidebar on his character describing "slow reflex". Instead of a debuff they have turned it into a buff, it isnt based on attacking a specific afflicted unit, instead it is a set chance of giving all units in your lineup extra attacks regardless of whether their standards are offensive or purely defensive in nature.

3:They have removed the limit to how many additional attacks he and characters on his team can get per round