You can insert cheats directly into the eboot as long as its not a memory patch (for example if you are patching the instruction that creates it then its fine but if you are patching a section of memory that only exists when the game is running then you can't), Decrypt the Eboot.bin first using "TrueAncestor SELF Resigner v1.98" then open it up in a hex editor and do a array of bytes search for what you are looking to patch, if you find it then make the changes and save and then resign it with the same tool, IF you can't find the correct bit then its probably in memory and you will need to use Artemis instead to patch the game as it runs, Good luck