My own current confirmed boon/banes:
Sharon - Neutral (of course duh)
Jeorge - Neutral (would have liked +spd or +atk, but eh, acceptable)
Lyn - -HP +Atk (always welcome)
Lucina - +Atk -Def (Very welcome)
Effie - -Spd +Def (HELL YES, second best variation she can get, best girl in team atm)