First off, do what Scarf said as he is quite right.
>That's a bad EV spread. Why not just do 252 Atk, 252 HP and 4 in a selected defense?
commented 56 seconds ago by Le Scraf
Another EV spread that would work is: 252 Atk/160 Hp/92 Sp.def.
The EVs are because of Intimidate that Granbull might survive a few physical hits.
Second off, yes it will work. Granbull has OK defence and a bad special defense stat so the AV helps with that allowing it to survive some special hits and potentially KO the other Pokemon.
As for the last slot, I would suggest Fire Punch for Scizor and Escavalier as they are only weak to fire and can really stop Granbull.
Hope I helped!
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