When I was doing affiliate marketing a decade ago, what I did manually was watch informercials and jot down the names of all those products. Then manually run searches in Google Trends to see which ones were spiking, and create content for those products (ie reviews, guides, etc). Here's an example of a product that really took off after they did an informercial in 2006: https://trends.google.com/trends/explore?date=all&q=almighty... . I created a page for this product and was ranked #1 instantly. Because nobody else was writing about it.

I stopped doing affiliate marketing so don't know what people do now, but just throwing you some ideas.

For sure. So shorter term. They're going to want to move faster than 3 months. Maybe like a past 30 day trend if possible? I would say also if there's a way you could dig into Alibaba and see if there's a bunch of new items of the same type getting listed recently that would be extremely interesting for them as well.