Yes, it would be useful, because Heracross' speed will be doubled when it is Baton Passed the speed boost
Heracross will be super fast if it is a jolly nature and his base speed will be basically 150 instead of 75, like Sep said.
I know you probably have your own set for Mega Heracross, but here's a suggestion:
Trait: Moxie ---> Skill Link
EVs: 252 Atk, 252 Spe, 4 Def
Also you might want to change your Baton Passer to Ninjask or Scolipede instead of Hawlucha. Hawlucha can do so much more instead of being a Baton Passer. Ninjask or Scolipede would be so much better instead of Hawlucha. But if you making a mono fighting team, which explains having 2 fighting types, then go ahead and keep Hawlucha as your Baton Passer.
Hope I helped!