Best engine for rendering 300 drones over 3D tiled buildings and elevation at 60fps

I could use some advice. I have a need to render 300 drones, all moving at once over a city (say, Las Vegas), complete with high-resolution 3D tiles/textured buildings, and over land that shows different elevations, all within a 60fps, non-jittering smooth display. That’s not even half of it - - - I also need to be able to show past and future trajectories, collision-thresholds, ability to follow specific drones, and render protected airspace. The goal being to show the highest resolution possible at the highest frame-rate possible.

I would like to know if I should use CesiumJS, Cesium ION, Cesium for Unity, Cesium for Unreal, or Cesium for O3DE. In a perfect world, this would all render in the browser. I doubt that CesiumJS would be able to pull this off at 60fps. I was originally thinking that perhaps the Unreal Engine with html browser export would help, but it appears that it discontinued.

If doing all that is not possible within a browser, that’s ok - - - I could just use some advice on which other engine to use. It sounds like O3DE is specially designed for this “pulling in real-world 3D data and using it within a high-powered engine”. If I don’t use ION, does that mean I lose out on all the 3D building texture tiles? Any advice is greatly appreciated.