"I still see her."
Translation:Ich sehe sie trotzdem.
It's not the nominative: the accusative of 'sie' (she) is also 'sie' (her).
that's not really accurate. Nevertheless implies a contradiction of an earlier statement. You need context for it. Still, by itself, only means a constancy. So this sentence only suggests that I continue to see her. If you add nevertheless, you change the context. She's in another country, but nevertheless I see her (or, yes, still see her).