If you're like 50 years old I don't see a problem with that
. You gotta take off the O and have a bit of a growl in your voice to make it authentic though.
It'd also be weird to say "nesan" to an elementary school student (unless she has a little sister who you are aware of... and the person you're talking to is aware that you are aware that they have a little sister). Another case would be if you are younger than the (female) person you're talking to (provided you are fairly close).
On second thought, you probably shouldn't go around calling people you don't know "nesan".