you didn't even bother to look at the tool section, did you?
for ff7, we have all sorts of editors. what you want to do is edit the stat curves ( and there is already a mod that does this and ramps up the difficulty considerably. As well as one other mod that just ramps up difficulty without editing stat curves. for PC anyway ) and the enemy stats which isn't really all that hard to do, just tedious
for ff8, I remember there being an enemy editor or something but the game has considerably less tools than ff7