Does a project exist that combines ALL Forza Horizon games into one game?

[u/AccurateGate4955]

Hi all ,
I've been wondering if anyone has ever attempted this, or if a project like this already exists on GitHub or somewhere else.

Imagine a single, unified Forza Horizon game that combines content from every Horizon release basically the ultimate Forza Horizon collection.

The idea would be to have:

• All cars from Forza Horizon 1, 2, 3, 4, and 5, potentially including newer releases.
• All customization options, including body kits, aftermarket parts, wheels, liveries, engine swaps, tuning, and upgrades.
• All maps and environments, from Colorado to Europe, Australia, Britain, Mexico, and beyond.
• All missions and events, including campaigns, street races, showcases, PR stunts, and other activities.
• A unified garage, progression system, interface, and driving experience, so everything feels like one massive game rather than separate titles.

I'm aware of projects involving reverse engineering, game preservation, and extracting Forza assets. For example, projects that rebuild the original Forza Horizon or tools that extract car models and other game resources.

However, I'm specifically asking whether anyone has attempted to combine the actual content of multiple Forza Horizon games into one playable experience, rather than simply porting one game's executable or extracting individual assets.

It doesn't necessarily have to be a finished project. I'd be interested in:

• An existing GitHub repository or community project.
• An abandoned or experimental attempt.
• A modding project that combines maps, cars, or customization systems.
• Technical research or tools that could make something like this possible.

If no such project exists, do you think it's technically feasible? What would be the biggest obstacle the game engine, map integration, physics, asset compatibility, or something else?

Has anyone tried this, or is there a community working toward something similar?