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Kise knows his former teammates better (and Kagami is just an exception). I believe Kise did once call Kasamatsu with a -cchi.

He adds -cchi to the names of peopke he respects.

It's pretty open to interpretation since aknowledge can mean a lot of things, although personally, I think Kuroko is saying that Kise adds -cchi to the names of people whom he think is a worthy opponent/rival on the court.

It is a form of respect kise has towards the person who he is mentioning or talking to. He adds -cchi at the end of a person's name because he has great respect towards them (mainly because they are proven to be strong).