I've seen some say they've gotten fines multiple times and others saying they've been doing it for years. Most likely you won't get arrested for it, but you could be fined, I have heard of it happening. Typically if you stick to older generations that aren't being sold, companies don't usually care. It's mainly when you start pirating new games that are on shelves still.
"NintenDON'T sue me please haha"
its been so many years since i first started downloading this stuff like youd think as soon as they see something illegal they would go after me but idk