Best Way to Fake Distant Terrain for Skydiving in UE5?

I’m working on a skydiving feature where players freefall over an 8km landscape. The playable area uses World Partition, but for distant terrain, I’ve been using a giant quad mesh (scaled up to 100,000) with a simple texture—no collision, just a cheap visual placeholder for the ground.

But I’m still wondering, what’s the best way to fake distant terrain in a case like this?

The HDRI skybox I tried was too low-res for my needs, and while the giant quad “works”, it feels like a cheap and bad solution.

Since players need to see convincing terrain while falling (and looking around), I’d love suggestions for a clean, performance-friendly solution.

Any tips or examples would be awesome, thanks in advance!

I found this tutorial a while ago, but I am concerned about how well it performs when rendering a giant sphere like this.