This is done fairly easy in Versus mode against a 2P with time set at infinite for leeway if needed.
What you need to do is select Kamui for 1P and whomever for 2P and then proceed to do the listed 4 different moves within round and then win. To be safe, try to get all 4 moves in the winning round.
Each move needs to be "ignited" by a primer move called "Kanugi" and then performed quickly after. To note, "Kanugi" will take a small chip of health out of Kamui. This move and the 4 required moves all can be done with "A", "B", and "C" attacks but for this guide I will go with "A" version ("square" button by default).
Joystick position is denoted by a numerical map of 9 such as follows:
789
456
123
Kanugi: 2, 2, "A"
then...
Kagesuki: 4, 1, 2, 3, 6, "A"
Kodama: Charge 1, 6+"A"
Seizan: Jump, 4, 2, 1, "A"
Sazarashi: 2, 1, 4, "A"
Perform all 4 moves (one at a time) and connect with the opponent and the trophy should pop upon the winning screen. You may need to have 2P jump so that "Seizan" hits.