I did *a lot* of cheats for the PC Engine via the HUGO emulator (long since discontinued) and they were all included in the distribution .ZIP file – under the filename CHEAT.TXT.
Each hack was done using HUGO’s built-in ‘action replay’ functionality whereby you could state a starting value (e.g. lives = 3) and then lose a life, do the search again and eventually find out where the lives counter was being decreased. Once you found the address in memory, you could then either change the value at the address, or freeze it so that it was not allowed to be altered by the game.
The file below is an updated version of the original text file from 2000, but I have converted into a Word document and then output as a swanky looking PDF with much neater looking tables. I’ve not changed the content much compared to the original text file, other than change/remove old email addresses and websites.
I have no idea if this work has been replicated in Magic Engine because, at the time of creating the file, I didn’t think Magic Engine had a similar ‘action replay’ style system built-in.