Aegislash
-Has 150 Def/SpDef while in sheild form
-Also 150 Atk/SpA while in Blade form
-Low speed which allow it to remain in Sheild form when taking damage
-3 Immunities
-9 Resistances
-Excellent physical sweeper
-Get STAB moves like Shadow Claw,Iron Head,Gyro ball etc.
Bisharp
-Good Atk Stats
-Has many STAB moves
-Has 4 X waekness against fight
-9 Resistance
-Comparitively low SpDef
-Good Def
So I would recommend to go with Aegislash which is really good.You can also play some mind games with it and its filled with strategies.
Aegislash @ Leftovers
Ability: Stance Change
EVs: 252 HP / 252 Atk / 4 SpD
Adamant Nature
- King's Shield
- Iron Head
- Shadow Claw
- Shadow Sneak
or altenate set
Aegislash @ Iron Ball
Ability: Stance Change
EVs: 252 HP / 252 Atk / 4 SpD
Brave Nature
IVs: 0 Spe
- King's Shield
- Gyro Ball
- Swords Dance
- Shadow Sneak