Nintendo Online with multiple accounts?

Following question:

I have a Nintendo Switch with two users on it. A main account of mine for which I also created a Nintendo Account and a second user for whom no Nintendo Account was created. Now I have bought the online function for my main account.

How do I get it to work for the second account? If I would now like to use the online service with the second account, I will be asked to log in or create a Nintendo Account. Is it still possible to play online with the second account even if I create an extra Nintendo Account for this?

The reason is: I don't play alone on the console and have created a new user for my sister to save the games. I just would like that she can also play online.

There are two versions of Nintendo Switch Online membership.

Single membership.
This only counts for a Nintendo Account.

Second, family membership.
This counts for up to eight Nintendo accounts on the same Nintendo Switch.

https://www.nintendo.de/...83143.html

So if you want to use the online functions with your second user / Nintendo account, you either have to sign up for another individual membership or do this for both users / Nintendo accounts via a family membership.
The cheaper option is family membership.

Supi, thanks for the precise & quick answer. Then there's probably no other option.