What are the Best Free 2D Animation Softwares?

I started out using OpenToonz, as it piqued my interest after discovering that Studio Ghibli uses it, but it is somehow a bit finicky and buggy. Now, I am currently using Blender, as it becomes easier to blend it with 3D aspects. I am saving for the EX version of Clip Studio Paint, but until then, I'm open to suggestions for other potential software I can use.