Kushina and Sakura now...that would be a nice conversation. They'd probably talk about Kushina's past and Sakura's love for Sasuke. She too would advise her about Sasuke as well, I bet. I'd like to hear that conversation.
About Naruto telling Sakura about the Sasuke thing...she already knows. It was given away when "Sasuke" (Naruto posing as him) had to urgently leave to the bathroom. When Naruto next ran into Sakura, as himself, he had to urgently leave again. It gave it away.
If InoShikaCho found out that Naruto beat Sasuke, I'm pretty sure they might be a little surprised, mostly Ino. But I doubt it would surprise Shikamaru.