Better Skill Inheritance for +Spd/-Def Nino

Well I have the same Nino, she's 5 star. I have this build:
Glimmer (Moonbow was not available)
Death Blow 3

Then her native skills otherwise.

Having a special skill on her is a little silly since with my current team build she's doing 68-72 base damage before WTA so she just one shots everything alive including quite a few (60% of) Hectors. She also ORKOs every red I've put her up against which is Marth, Lucina, and Young Tiki of all builds. Haven't had the chance to see how she fares against Ryoma. But I have a TA M Robin for him if she can't take him out by herself.

For reference the skills I put on my home team to support her are: Hone atk 3, Hone spd 3, Fortify def 2, and Rally Resistance.

I just put Luna and Wings of Mercy 1 on mine from a Frederick. That way she can teleport right behind a unit that got attacked up close and finish the attacker off safely. You could go up to Wings of Mercy 3 and Moonbow if you're willing to make that kind of investment in her (5 star Palla on top of what's already done with a 4 star Frederick can complete that), I just don't have the resources to do too much more right now. But, you should also pair her up with Eirika if you can. Att +3 Spd +4 and add on Rally Def or Rally Res for that +4 to give Nino a total of 60 attack, enough to kill even most red units if she can double them. Which is easy with that speed IV and Eirika. If you're having problems with a specific type of unit, you could consider giving her a breaker type B slot move, and there's always stuff like Vantage/Desperation to give you a little edge if you're lower on health from taking on another mage or something. If you want her to be even more of a glass cannon, Life and Death is ridiculous on her. Doubling everyone and OHKOing several, ORKOing almost all the rest, is pretty fun. I like Hone attack 3 on her personally. A slot could be modified to Fury or L&D if Res+3 isn't your favorite option. Fury works well if you're going for a B slot move that takes advantage of loss of life, and/or decide to give her a special like Vengeance/Retribution. Basically, lots of viable options, just find one that suits you that you have the resources for, and don't feel bad about stopping at just using up a single Frederick (or Palla for Moonbow) for now like I have.