Two years later, and World Partition still doesn’t support static lighting.
I really hope it will be included in a future version, and that Unreal Engine won’t abandon static lighting entirely. 
Don’t forget, you can voice why this is important on the Unreal Engine Roadmap:
https://portal.productboard.com/epicgames/1-unreal-engine-public-roadmap/c/1247-static-lighting?&utm_medium=social&utm_source=starter_share