>>120285670nadeshiko is as good as what you do with her. theres so many ways you could go about it since its an assist. assisting in what could be a mix up, getting space, protecting yourself, or punishing something.
a simple set up could be if you call her from above and dash at someone. if you quick call her and they jump she hits and you can combo air throw, you long call you can air throw them if they jump or command grab them if they sit there.
she always comes out even if you get hit so you could wake up with it and if someone tries to combo you they either drop it to block or get hit and you combo from that.
she can also otg which is nice to have if you can set it up for possible stun or ko.
if ken does fireball you can instantly quick call her and punish and im pretty sure you can use her v skill to get guage if you choose not to go in afterwards
if you just throw it out then it loses a lot of its effectiveness if people dont panic over just the activation
nash is simpler because its a good combo extender, you can punish long range stuff, you can escape danger if you teleport to get out the corner; if it hits you get a combo but if they block its a side switch which isnt bad.