Some Switch ports sacrifice visual fidelity. The NSP is the one that retains the film grain, lens flares, and the "cine-lut" filter. If the NSP release notes say "Removed film grain for performance," skip it. The grainy black-and-white look is the entire point of the game.
Look for scene release names or trusted community posts with these details: trek to yomi nsp best
Assuming you have a modded Switch (AMS 1.6.2 or higher), here is how to ensure you get the "best" performance from your Trek to Yomi NSP. Some Switch ports sacrifice visual fidelity