Trip to Brazil in September (Rio, ilha grande, Lencois Maranhens, iguazu falls)

My boyfriend (M22) and myself (F20) go for an annual out of Europe trip every year (we live in Europe). We've previously been to Indonesia and China in September, Florida in November, Australia and Dubai in December. This year we can only travel mid august or September. We're planning to go for around 16 days including travel days. Due to the current situation and also monsoon climates we're not choosing somewhere in south east Asia but trying to find somewhere else and like the idea of going to Brazil.

I'm quite ok with planning what to do, where to go, what to see, ect. I'm just worried about the rain and weather temperature as I'm not finding much information about it. From what I've understood there would probably be some rainy days, and that's ok. I just want to know if maybe it wouldn't be as hot as we would like since quite a few of our plans would be based around the sea for eg beach days, boat trips ect. We would also want to try the paragliding or hanggliding while we're in Rio and that's very dependent on the wind.

I know it's a bit early to try and predict the weather but some understanding of it would be great, to see if Brazil is an option for us or not, as we're young and want to make the most out of this big trip. We loved Indonesia in September the weather was warm and sunny perfect for the beach activities although we did get 2 days of rain. We also aren't sure if travel in up north to Lencois Maranhens would make sense or not.

I would appreciate any advise or tips regarding this trip 💗💗