HammUEr, a Hammer/Worldcraft map importer for Unreal Engine

If you are just using CS:GO maps, then perhaps use BSPSource - Valve Developer Community that Valve recommend.

Then, import into 3D MAX using WallWorm (VMF), and export via datasmith=>UE 4.23 import.

Depending on the map and entity depth, you may need 32-64 GB of RAM to complete, but it will work.