Godeaters Of The Astral Sea is a cosmic whalepunk setting for What's Old Is New.
The PDF is 24 pages, with clean and well organized but bare text.
Contents-wise, a chunk of Godeaters is system neutral, but a lot of specific guidance is given on how to conform it to WOIN's baseline expectations.
Flavor-wise, Godeaters is quite flavorful. You're cruising around a weird cosmos on out-of-date sailing vessels, extracting blood from the husks of dormant gods, sword dueling pirates on deck, etc.
When the lore and mechanics interweave, you get good results. The aforementioned god husks are dungeons, and retain some of the original god's portfolios, making them very flavorful dungeons.
A lot of the hazards you can encounter while cruising space are also very conceptually cool, like shoals of clotted dreams.
I do feel like Godeaters could be expanded and formalized a bit more, but as-is it's a very useable document packed with tables, and its alterations to the core WOIN mechanics feel reasonable and interesting. If you're already comfortable with WOIN, or if you like whalepunk and are cool with learning WOIN, I'd definitely give this a look.