So recently I discovered that it is possible to use the Super Juggles cheat during an All Endings run in Tekken 2.

To do so, have a second controller attached, and before you select a character, hold Select+Up on the second controller. Then hold Select between each round. If you don't, you have to hold Select+Up in-between rounds again.

This cheat only works after beating the game with All Default Characters. I've separated the board into 'Cheats Used' and 'No Cheats Used' to reflect this.