What's under the proposed floor? The only thing that will be waterproof enough to seal the subfloor is tile over a decoupling membrane. Porcelanosa PAR-KER is a quality product. They also have other surface looks in large sizes. Tiles, Bathroom and Kitchen Equipment | Porcelanosa and Ascot Arce - Ascot - PORCELANOSA Grupo

Quick Step Essentials is the most water resistant laminate. Nothing is water proof if the subfloor can be susceptible to water damage so sounds like you should be more concerned about slip resistant if people are dancing straight from the pool. A tile may be the better solution for you.

You are looking for porcelain tile, not laminate. Look at Saddlebrook XT for maximum slip resistance.

https://www.daltile.com/products/Wood-Look/Saddle-Brook-XT

Sure, tile would tick the durability boxes, but not comfort or looks. I'll use tile on the patio. Inside I'm still going for something that simulates real wood as closely as possible in terms of look and feel.

It doesn't need to be bombproof, but not bubble up if liquids are left standing for a few hours, doesn't scratch easily, etc. Our cheap laminate has withstood parties with people dancing with dirty shoes surprisingly well in terms of scratch resistance. But it bubbled up around the edges where there were standing spills. The areas that were scratched were due to heavier damage. If high quality flooring improves that, and fixed the bubbling, I'll be happy. I think high quality waterproof laminate or luxury vinyl plank should be better than what I have.

Downstairs we have concrete slab, so there should be no issues. Upstairs is wood subfloor of course, but we're not gonna be spilling stuff upstairs. I've also considered using engineered harwood upstairs for the nicer feel. Whether the stairs should also be hardwood or not is another question. Getting a close match with the downstairs flooring might not be easy. But getting a nice square nose on the stairs seems easier with wood than planks.

Looks like Nucore Performance is more scratch resistant than Flooret.