2 Switch users (profiles) with a Nintendo Account playing online together on a Switch?

I have had a Nintendo Switch for a few days and created a separate user profile for my partner and myself on the Switch. I have already linked my profile to my Nintendo Account, my partner does not yet have a Nintendo Account. However, we would now like to play together on a Switch Online, for example Mario Kart 8.

Do you have to solve this with two different Nintendo accounts with the family function? Or is it enough if I buy Nintendo Online via my profile / Nintendo Account (without the family function) and she can then also play online on this Switch with her profile without a linked Nintendo Account?

If your user profile now also needs to be linked to a Nintendo Account, can you also link to my Nintendo Account and play online on the same Switch at the same time? (Linking to my Nintendo Account seems to work, at least I could click on Link if I also enter my Nintendo Account via your profile). If that works, the next question would be whether both profiles could then play online at the same time on a switch using the same Nintendo account.

I hope my problem is halfway understandable. Basically, it is simply a matter of whether you can play with two profiles on one switch at the same time via an online subscription or whether you have to take out a family subscription with two different user accounts for two profiles.

No. I think this way would not be as compliant with the guidelines either.

I suggest you take out a family subscription for one year. It costs 20 euro, but it's a cheap price for a year.