I literally don’t know what our money look like. I have a vague memory that the 20 krona bill was blue, but beyond that I don’t know.
My final question in that comment is very sarcastic. I know absolutely nothing about Swedish money but I can guarantee you that it does not expire.
Assuming you’re serious, and you have no idea what your own currency looks like, could you not just go to a bank and make a withdrawal in cash and keep it somewhere safe? You don’t really need to know what it looks like as long as you get it from a trusted source.
From an ATM maybe, the actual bank offices don’t have cash. But the question is, what would I do with the cash, only a few stores like big chain grocery stores accept cash nowadays in Sweden. Small stores and cafés etc almost never accept cash as payment. Even beggars outside on the street often have a QR-code for their mobile app transfer because so few people carry actual money.
Put it somewhere safe. It doesn’t expire. You don’t have to use it until/unless there’s an emergency.