I modded it by myself, changed the threshold to 1, started a new campaign with Macedon, fought with the Indenpdent Gauls at the north, heroic victory, and bam. Victor in Europe. XGM marathon mode activate lol.
Edit: BTW, I have a suggestion. I think that the Legendary Commander trait and those that precede it are unrealistically (IMHO) difficult to obtain for it requires you to win 96(!) battles to have it. I suggest you to make it 2, 4, 8, 16, 32 (what I did).
Thoughts?