Some players associate Unreal Engine with optimization issues, but you can use it and have stable FPS, as developer Michael Simard proves in his experiment.
He replaced UE’s grass system with a GPU Procedural Content Generation (PCG) solution he’s been developing for Calysto World 2.0, a tool designed to help you create large-scale procedural landscapes, forests, and biomes.
Simard’s tests show that while the default grass produces 15 FPS, his solution brings it to 60 FPS. The difference comes from moving the detail placement fully to the GPU, he says.