Plant types that are adept at growing in water are called Hydrophytes, and some examples of ones that can grow well in water are wild rice (Zizania), water caltrop (Trapa natans), Chinese water chestnut (Eleocharis dulcis), Indian lotus (Nelumbo nucifera), water spinach (Ipomoea aquatica), and watercress (Rorippa nasturtium-aquaticum).

Contrary to popular belief cranberries don't grow in the water, they grow on the soil, but they are a good example of why you shouldn't just assume all the marsh area is going to be underwater as they are grown in sandy dirt near water and then they are transported via the waterways later.

That being said, due to the fertility of the soil in marshlands, if you can find some not quite flooded land to grow crops in it would be easy to grow other types as well, and if you notice in the tribe writeup the To'resk have adapted to grow food like rice in the water, and to grow other crops outside of it also.

TLDR, I wouldn't stress too much about have diverse crops in the wetlands.

I hope they will make a type of fruit that will grow under water and sprout above so you can see the fruit. Or maybe the fruit can be a giant leaf looking thing that is like a thick leaf with some seeds and sweet stuff in the middle. Kind of like a thin kiwi. That would be cool