Although you don't have a formal job, you still have to bring something for your nephews and nieces when you go home, because the amount of things is not important, what is important is your intention, which is actually a way to enhance the relationship between aunts and sisters-in-law.
But you must consider your financial ability. You can't buy something too expensive just to save face. This is actually very immature.
So what to give? Personally, I think it's better to give a teddy bear doll. The most important reason is that children like it and it is safe. In fact, many plastic toys are unsafe now. Buying safe and non-toxic toys is the demand of more and more parents, and if you give a teddy bear, it is safe and fun, and the most important thing is that it is not very expensive.
Well, as an aunt, your intention is very important, and your sister-in-law will also think you are very sensible, so come on, your nephews and nieces will definitely like it.