There are roughly one zillion icon packs in the Play Store, so do you actually need more? OnePlus thinks that, yes, you do. It has released three icon packs in the Play Store for use with its own OnePlus launcher. While not technically new, they're new to the Play Store.
The icon packs in question are the standard OnePlus icon pack, OnePlus square icons, and OnePlus round icons. Applying them is as simple as opening your home screen settings. The new icon packs are included in with the build of OxygenOS on the OnePlus 5, but now they're available in the Play Store. That indicates OnePlus will update them, which they certainly need. None of the icon packs have very many custom designs, and the way they handle third-party apps is awkward.
The only addition to these icon packs compared to the pre-installed version is dynamic icon support for calendar and weather. These icon packs will only show up in the OnePlus launcher, and the Play Store will only allow installations to OnePlus devices. I doubt people will be clamoring to get their hands on these icons anyway—there are better options if you're into icon packs. Still, having them in the Play Store could allow OP to add features and new icons over time.