The following cheats work BUT (huge but) completely remove all items from KEY-ITEMS tab, which is not a good thing to happen. And yes, even if you just activate only 1 of them, the Key-Items tab is completely emptied out. Good thing I made backup-save.
- Have All Consumables
- Have All Accessories
- Have All Fusion Items
- Have All Items
Good to know. Basically use them right at the start of the game to be safe if that can't be fixed. Hope we can get all materia option as well. Would be nice if a save editor is made at some point. I don't remember if the original had one or not.