In my personal survival world, I have actually found and recorded the location of 82 separate villages (only including 1.14 or newer), and have not found a single cat of the "Jellie" variant.  At first I figured they were just rare or I was unlucky, but I now have every advancement except A Complete Catalogue (tame all cat variants).

 I spent some time on sites such as reddit and learned that I am not the only one who is incapable of finding Jellie cats

They can be spawned using the cat spawn egg, about as frequently as other variants.  However, I do not think they are spawning in villages at all.