Actually, I don't think there is any potential for "Godly Villains" EVER, again...
The key to combine Bijuu back into the most powerful-by-default being (Shinju/Kaguya), is sealed in another dimension.
At least as far as i know, Chakra is not some self-emerging, natural pool. It all derived from Shinju, and it all ends with it.
You have Bijuu still split in Narutoverse, but the key to bring them back into something chaotic and Ultimately the most powerful being, is sealed in another dimension.
If there is someone suddenly arriving, who is somehow, independently stronger than Kaguya/Shinju, it would be an asspull.
(At least as long as it is not some aliens from another dimension arriving)...