Wrath to who?

I have finally pulled a single Nephenee and am torn who to pass her amazing Wrath skill to. The two units I am looking at.

Black Knight +1
I do not have a B!Ike to pass Steay Breath to him also but might in the future after giving my Nowi Steady Breath first.

Arya +Hp -Atk
Haven't passed anything to her besides reposition and threaten speed. She is standard.

It's hard for me since I use them both tons. So please give opinions on if I should go with the Black Knight or Arya for this rare Wrath skill pass. Thanks.