yes this would definately pressurise india, but i don't think that either india or pakistan would like to risk a referendum, neither of the army would let that happen, taking history into consideration.
strategically pakistan can't hang Kulbushan Jadhav due to lack of evidence, they need some solid arguments for capital punishment, i know that pak army can run trials on pakistanis that way but this is an international situation, things don't go "pak army" way here. And still if pakistan manages...
please tend to learn about someone before demanding his/her execution dear pakistanis, his last name is Jadhav, not Yadav.
And before calling him a terrorist kindly give me video link by any independent media where he is shown carrying ak47 and shooting civilians in pakistan, it would be more...
i don't think that this would be happening soon, as per the international laws pakistan would have to allow to present defence by india. Hanging someone is an extreme punishment and there has to be a credible process before such a thing could happen.