Just because they look the same doesn't mean they are the same...
Meal-worms (Tenebrio molitor) have thicker shells and have barely any nutritious value.
Superworms (or morio worms, Zophobas morio) have shells that aren't as thick and have better nutritious value.
Meal-worms thick shell can cause impaction to your chameleon.
Both don't make a very good staple feeder, but as a treat the superworm is far superior to the meal-worm.
As staple it's better to use roaches like Dubia or Orange heads, crickets can be used too but if your animal takes roaches I'd definitely use that as staple because they are way cleaner and less smelly than crickets, much easier to breed on your own and have better nutrition as well.