Finally managed to get Platinum trophy of Onechambara Z Kagura (with NoNoNo!). According to PSNTrophyLeaders, I did it in 2 years and 1 month.
Not sure if I would get Onechambara Z2 Chaos for PS4 in the future. It seems to have better visuals (no more jaggy shadows) and more high-speed action (like how you can dash toward locked-on enemy).
But yeah, at least I wouldn’t feel guilty about buying it since I already completed the first game. I just hope they tone down ridiculous Quest requirements.
The next game in my quest of completing DLC add-on trophies seems to be Metal Gear Rising Revengeance… (although I might change my decision…)