Welcome from another southwestern Ohioan! Warning ... bananas are heavily addicting!
Absolutely follow the advice of putting them out and gradually acclimating them to the sun ... old umbrellas work well if you don't have much in the way of mildy shady areas to move them around to. As far as planting in the ground this late in the season here, I'm on the fence, but am leaning towards suggesting you leave them in the pots. Since they are small and our season is winding down, the mild shock of re-acclimating them to the indoors before the first frost might be enough for them. When you add in the possibility of breaking off new tender roots when digging them up to repot for winter, it might be a bit too much. Once they get some size to them, they're quite forgiving, but the little guys, not so much.
Like you, I also grow cannas and elephant ears ... I just love having the tropics in my back yard!
Happy growing!
Annie