The general thing people do to avoid bans is use an Emunamd and block all Nintendo servers. Emunands are basically just a copy of the internal storage of the Switch that runs on your SD card. Having it run like this means you can keep your Sysnand clean. The Sysnand is what you keep stock and never use CFW on. Even this has ban risks though. Doing anything has risks.
Only true way to avoid a ban on your console you want to be able to play online on is to have a second console to run CFW on.
If you have CFW in your emunand, with incognito or 90dns, and a clean sysnand then you're pretty much invisible to them. I've been doing this for several years already and I'm not banned. You can do anything to the emunand and feel safe, but as you're blocking Nintendo servers you won't be able to play games online.
If you're using CFW on your sysnand. I'd say they can strike you with the banhammer at any time. Especially if you modify save files, install nsp/xci files, or enable cheats, mods or sysmodules while playing online games.
Simply having atmosphere won't likely get you a ban, but you would still have a dirty sysnand and there's simply no guarantee of ever being safe from a ban.
Cfw alone is very safe, atmosphere is designes to allow going online with it.
Only importend thing are, don't install nsps/xcis, don't cheat online.
Also be careful with modding games, either stay offline while using them, or carefully check what's safe in a game to do online.
I think in smash for example there where ways to play online against friends with mods, but I never looked more deeply into it.
Nothing, not even airplane mode, is absolutly 100% safe. The problem is that just because there are next to none publicly known cases of Atmosphere itself leading to bans, does not mean its safe. It just means its unlikely.
Nintendo didn't hand us a rulebook about what is a bannable offense and what not. No one in this forum or on this planet can claim to exactly know whats going on, except for the people at nintendo that that manage this kind of thing (devs or whomever). The only thing you can say is that everything you do is risky. And every risks you take stack up and increase the chance of you getting a ban. Some things might be less risky, such as clean atmosphere - others have a higher risk, such as installing NSPs or forwarders. The only person who can decide if its worth taking the risk is the console owner.
Why am i saying that not even airplane mode is 100% safe? Well, the more unlikely case is that you (accidentally or not), a game or a homebrew could change the internet settings. There is no guarantee that this will never happen, thus its not 100% safe.
The other, more likely reason is that console owners can use emunand on airplane mode. The same risks from above still apply but also, that with a system update on your sysnand nintendo will introduce new telemetry domains that 90dns does not block yet or even worse, instead of a domain they use an ip adress, which cant be blocked at all. (by a DNS service)
They could also introduce mechanisms that read the sd contents and report it back somehow.
And just because they dont do it, does not mean they will never. With the 13.0.0 firmware update, they introduced a mechanism that will change console settings whenever nintendo wants to. This might not be interesting for people that use the mitm dns host file thingy that atmosphere introduced but it does not help against new telemetry domains they can introduce.
All in all: There is a good chance that nintendo will not have you on the radar if you take security measures and dont do stupid risky stuff with your switch. Being 100% safe is not a thing though.
Can someone explain me how to use à CFW on a emunand ? my current switch is banned but it doesn’t matter because i was playing only solo games…buying games is not an issue for me but i want to keep the possibility to switch the game in docked mode + overcloking for my pre-ordered oled switch
yeah it's not like the good ol days of the 3ds where you could mod your pokemon saves (directly) and not get banned for a work around i have 2 switches 1 modded/banned and one virgin switch it's teedious trading back and forth but none the wiser
Why would blocking all nintendo servers be a problem if you dont want a ban? The whole point is not connecting to their servers… Why on earth would you take a dns that only blocks some servers?
You have me utterly perplexed.
On a sidenote related to the OP. If you wan’t to play smash bros online with other people & ACNH aswell you cannot without a ban. If you just want to mod the games you can, but the only online you can use is homebrew related.