A little background. I'm a Malay living in Malaysia. Disney Plus released here some weeks ago.
It seems that Disney Plus isn't available on Panasonic Smart TV, after hearing from a friend. Though, what about Panasonic Android TV? You should be able to download it since it runs on Android, right? No?
Yes, Panasonic TVs with certified Android TV will have Disney+ available in the TV Play Store.
If they are running another OS, Disney isn't available.