Their 133 lbs is the UFC's 125. There is no difference. They don't allow (massive) weight cutting after one of their fighters died cutting weight.
"ONE FC’s new weight cutting rules includes random hydration checks on fighters to ensure that they’re not cutting a lot of water weight. Fighters also have to weigh at their fighting weight during the entire week leading up to the fight. Both rules as well as others will minimize the amount of weight that fighters will cut overall, thus improving the fighter’s health.
As a result of these different weight cutting rules, ONE FC also changed their weight classes slightly. In essence, each weight class will have an upper limit that’s about 10 or 15 lb higher than the weight class with the same name in the UFC"