+hp Shiro or +spd?

Hey! I’ve kinda stuck. I have invested in a +hp -res Shiro but today I got another Shiro and it was +spd -res and I don’t know which one to use. My build is dc, qr3, def tactic 3. I don’t know if I should +1 the one I invested in(+hp) or +1 the new one and give it the skills on the one I got(+spd).