Hana IV question

Honestly, I vote +Atk in this case. Hana has such high base Spd, and with a +Spd refine on her Wo Dao+, she can hit 52 Atk and 39 Spd unbuffed. Running LnD or Fury would help even more in terms of offfense. What A Skill were you planning on using? Besides that, she has very high merge potential so you can still boost her stats easily that way.

+Atk/-Res is really good on her. Plus it frees up sacred seal and weapon refine, which normally just grants +2 Atk for melee weapons. You would rather take the Spd refine so it's a +3/+3 Atk/Spd basically with your Atk boon. Her native LnD allows her to go even further but at least she can hit harder.