This is like the fake food you see outside Japanese restaurants but with Nintendo characters.
YouTuber Nendo Zaiker-Snail created this Mario sushi from polymer clay. You can watch the process in the 12-minute clip in Japanese below.
What really stands out is how this seems possible with real sushi. Make the mario logo with tuna for example, Tamago
Nendo Zaiker-Snail has other Nintendo themes Fimo creations like this Kirby breakfast sculpture.
Which looks delicious.