Can fortnite run in browser?
Would be nice if they could just do that and show genzoom that they dont need to discover interesting content via an appstore app only.
Currently learning webdev, so I'll give the best answer I can:
You could probably use canvas and recreate all of Fortnite, but it would be a remake, not a simple port. There are existing libraries that could be used to load models and perhaps animate them, but... it would take a while, and there would be major FPS issues. Javascript is much less efficient than native apps.
Unreal Engine (and Unity) can target HTML5 / WebAssembly. I expect the main issue is the download size of the assets.