Not so. Changing the basic database removes the possibility of playing it online. It's not just the cars.
But I can suggest you to try playing split screen. That way still works
That's what I was referring to, just some color changes, not even textures. Keeping the structure of the 2014 car, with the 2024 colors... that wouldn't change the game's databaseThere would have to be a Mod that Replaces only Textures, Sounds, and Liveries... No performance changes, 3D Shape changes, Track Layout changes, any of that, Only that way it could maybe work, and of course unfortunately, the changes would have to be much less noticeable :-/