So, for starters:
Cradily:
- Nature: Careful/Sassy:
-Item: Leftovers
- Moveset: Choose what you like between: Giga drain, rock slide, earthquake, recover, stealth rocks, toxic, etc.
Druddigon:
- Nature: Impish (Could be adamant but you lacking a phyiscal wall)
- Item: leftovers /Rocky helmet
-Moveset: Choose what you like between: stealth rock, dragon tail, glare, toxic, eartquake, fire punch (Dtail + stealth rocks are essential tho)
Empoleon:
- Nature: (Modest/Timid/Or any mixed nature)
- Item: Life Orb, Choice specs or expert belt (depending on set)
- Moveset: Surf/Hydro Pump ; Ice beam; Grass knot; Earthquake / Aqua jet if mixed; Agility if you want a late game cleaner
Arcanine:
- Nature: Jolly
- Item: Choice band probably the best one (Orb is good too)
- Moveset: Exspeed; Flare blitz; Close Comat; Wild Charge
Alakazam:
Good question. Go try around I guess. Nature is timid tho.
Heracross.
Nature: Jolly /Adamant (If scarf)
Item: Flame orb or choice scarf
Moveset: SD(NON-scarf) ; Megahorn; Facade; Close Combat; Night slash ; Stone edge(For Scarf). Choose 4 of them depending what you prefer.