After you get Yanma in safely, which is very difficult even though it resists its STABs 4* because of that awful 45 base defense sticking out like a sore thumb. Even after it gets in, Heracross could easily switch out to one of the many things in UU that can wall a Pokémon with bad type coverage and only 75 base SpA. Registeel, Milotic, Moltres, Mismagius, Rotom and so much more can all easily take a hit and OHKO next turn, or you can switch and have them set up on you. On top of that, you will most certainly need a spinner, and attempting to spin so your "counter" can actually counter the Pokémon it is supposed to be countering seems a bit overkill to me, and if you went this route you mine as well use Moltres.
You would be better off using a Golbat, who has better Defenses, useful utility outside of forcing out Heracross, and access to Super Fang as well as Brave Bird, Taunt, and Roost.