Btw, what are your feelings on the idea of Oshus and Wind Fish being the same deity, just in different timelines?

I... kind of hate that idea? It just rubs me the wrong way. I kinda of dislike the general idea of similar deities in the Zelda series being the same thing simply because they're a little too similar. There's three separate whale deities in Zelda and I wholeheartedly believe that they're all distinct, separate entities.

Plus, while there are similarities, being that both of them lord over a sort of alternate dimension, where the outsiders enter via dreams, there are also some differences that make them differ too much for them to just be alternate timeline versions of each other. For one, they look different, which isn't much, but is enough for me.

How they generally work is also the biggest reason why they just. Are not the same thing. The Wind Fish seemingly only holds power over Koholint, while Oshus's domain includes pretty much an entire alternate Great Sea. The Wind Fish is more or less alone as the sole deity of Koholint, while Oshus operates along with the three spirits, that frog, and the thing that upgrades the spirits.

Another similarity is the respective enemies, the different bosses pretty much being extensions of the main villain, but Nightmare and Bellum are... certainly not the same, either, and I'm bringing these two up since they're pretty tightly connected to the Wind Fish and Oshus.

PLUS when the Wind Fish 'wakes up' everything goes away. The only exception being Marin if you win without dying. (I don't know what the Wind Fish has to do with that and I do not have enough investment in Link's Awakening to go into it.) Oshus is awake the entire game and the condition for Link and the others to leave is simply just. Oshus letting them go home after seemingly deciding the amount of time that has passed for them. (I very very strongly believe that Linebeck is originally from the same world as Tetra and Link and there's a lot more to this but that is not what I'm talking about here)

Even further, Koholint seems to be contained within the Wind Fish itself, since after it disappears Link seems to see it afterwards. On the other hand, Oshus seems to be within his own world instead, the inverse, especially since it's implied he and other entities within can reach out and interact with the worlds it is connected to. (Bellum creating the Ghost Ship and it showing up in Link's Great Sea)

I just feel like they operate too differently and the things and entities surrounding them are too separate and too different for them to just be. Alternate versions of each other.

There also isn't much evidence to suggest that an entity could work differently than an alternate version of itself, and it really just doesn't make a whole lot of sense anyways, since Oshus and the Wind Fish are generally pretty separate from the main Hyrule, so whatever goes down there won't really impact them a whole lot.

Also I think that whatever goddess creates the minor deities within and related to Hyrule just really likes having whales as protectors of small worlds.