nothing to worry here. move along

 

If a console is hacked, you always risk a ban with everything associated; console certificate, Nintendo account, and cartridge header. Doesn't matter if you own it or not. Nintendo cares that you hacked the console because that means you violated the Terms of Service which will lead to a ban. Don't hack the console if you want it to be safe.

 

Nintendo has the ability to ban game cartridge headers as well as consoles. The risk still remains. Its greater if it was used since you have no idea if the previous owner(s) dumped and actively use them.

 

Do you plan to keep your hacked console in Airplane Mode?

 

Then as long as the hacked console never connects online, your friend can play it without any worries so long as he doesn't provide copies of the header to other people.

 

Your friend is 99.9999999% safe. Nintendo isn't going to ban a console because it used the same physical cart that you used, ESPECIALLY if they never even knew it was in your console.

If your console did get banned, and if they logged certs of every cart you and your friend ever used...don't panic, just take off the last three 9s, your friend is now only 99.9999% safe. If you backed up your cart to xci (and explicitly backed up its cert), and Nintendo is able to determine that you were playing it as an xci (it seems they can't as if yet, but there's no guarantees), then I'd say your friend is about 99.7% safe. The cart though, not so much.

The actual danger to your friend's console would be if you both played online using the same cart at the same time (obviously, one of the consoles is modded and actively pirating). Even then, I'd wager money that your friend's console would not be banned, and that the cart's cert would PROBABLY not be banned.

 

From what I understand, what you are asking is if modded/hacked Switches leave traces of hacking/modding in game carts.

No, afaik, they don't.
Afaik, carts are readonly, and any data related to the game (e.g. saves) are stored only on your Switch's NAND.

In your scenario (where you will never go online with the hacked Switch), the ones who will borrow your carts have no risk.

BUT if you ever go online, and have used a cart dumper homebrew on your carts, this thread might be of interest to you:
https://gbatemp.net/threads/ban-reports-on-2nd-hand-games-played-on-non-modded-switch.519986/

 

You guys are awesome, thank you very much for the answers. I have no intention of ever attempting a dump or going online. I'm sure someone out there (who is also lurking) were wondering the same things.