This is nowhere near reality.

Even if you could just “translate” code from one language to another, that ignores asset pipelines, asset store libraries, and all the build pipelines that allow you to ship cross-platform.

You also need to now train your entire dev team on a new tech stack.

Switching engines is an enormous effort

One of the biggest appeals of modern gane engines is that you barely need any code but that also means everything is centered entirely around the game engine, I doubt there is any way to transition that, it probaly means devs have to start from scratch and reimplement the mechanics.

I’m using Godot 3 for my current project because even the relatively minor changes I’d have to make to port it to Godot 4 would be unfeasible. If I had to change engines entirely I’d have to just abandon the project.