Here is a little tutorial for how to setup the codes you need. First off you will need the codes for Unlock all characters and Stages (If you haven't unlocked everything already. Universal Control Fix (UCF) 1-P C-Stick. Tap Jump Off and Hyrule RNG Code (for Adventure) also known as Forced Triforce Room Location. All these are optional of course but i will share every code as well as how you put them into Dolphin

Open Dolphin. I use the 5.0 version so there might be some slight differences. First of all you need to click on Config and click on Enable Cheats. After that find your Melee iso, right click it and go to Properties. Select Gecho codes and click on Edit Config. Go to where it says [Gecko]. If it doesn't say it then make one at the bottom of the .txt file. Copy the codes under [Gecko] and go paste them under the [Gecho] You created. Or just copy and paste. Link to codes: http://www.mediafire.com/file/lzgwad8a33nd1je/Melee+Category+extentions+codes.txt/file

I have put the Hyrule code to be in the room that is down to the left. Number 4. But if you want to change the room then you can edit the code by doing this: https://smashboards.com/threads/hyrule-adventure-maze-forced-triforce-room-location.398561/

Save it and go back back to the Gecho Codes. At the bottom you will see your codes. Just enable the ones you want.

(Sidenote. There are possibly more codes to come. When they do i will update the file and the guide to include it)