You can launch Trailmakers directly from the installation folder (e.g., \steamapps\common\Trailmakers\Trailmakers.exe ) bypassing the EAC launcher. However:

The only thing Creative Mode lacks is the progression of the campaign. But if you are trying to cheat scrap, you don't care about progression—you care about building wacky vehicles. Just use Creative.

For more complex hacks like speedhacks or infinite build limits, users often create Lua scripts Cheat Tables (.CT files) You can find community-made tables on the Official Cheat Engine Forum or sites like FearLess Revolution.