Legendary Lucina to keep and merge

I have 2 L-Lucina, +HP -Def and +Atk -Spd

what IV do you suggest to keep.after the merge
The build is basically the following
Lucina
Weapon: Thogn
Assist: Future Vision
Special: Moonbow
A: Swift Sparrow 2
B: Swordbreaker 3
C: Distant Guard 3 or any other
S: Heavy Blade 3 or Spd+3 ...or any other??