Q.Whats Wrong With My Banana Plants
Very slow growth, odd leaves

Certified GKH Gardening Expert
This looks like a Fusarium infection. A very severe one. This is going to be a challenge. If this is the case, which you can confirm with your local extension service, then this is not likely going to be cured. This can only be managed. And it is not likely going to be managed successfully, unfortunately.
These articles will offer information, as well as a way to find the closest extension service to you:
https://www.gardeningknowhow.com/edible/fruits/banana/fusarium-wilt-in-bananas.htm
https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm