I doubt any real harm would come from feeding them, as a treat. Overall they're probably too chitinous and high in fat to really be fed to aquatic and semi-aquatic frogs.

Your frogs would prefer softer bodied insects and worms, I wouldn't feed them for fear of bowel obstruction but I am pretty cautious with what I feed my frogs.

I do treat crickets for my ACF but these are not nearly as chitinous as mealworms.