Hmm. You could try! Most dragons are a bit picky and refuse to eat any bugs that aren't moving though. So it does depend on the dragon.
Have you considered other feeders? Phoenix worms (aka Reptiworms or Calciworms), appropriately-sized hornworms, silkworms, and Blaptica dubia roaches are also good feeders for dragons. If the bearded dragon is longer than 16" you can try Superworms too. But no mealworms ever! They're not very good for dragons despite what the pet stores may try to tell people.