You can try to teach her the command 'no sniff'. Start by using it on walks, when she stops to sniff something.
I had a GSD rescue that was a very dedicated sniffer. When you took her into a strange room, she wouldn't settle until every square inch of the room had been sniffed. She was also a crotch sniffer, and we were never able to break her of the habit. I think I might have been able to do it on my own, but I was married at the time, and my husband was more, um, forgiving of her behaviour than I was.
He often commented about how accurate she was when she sniffed his crotch. She'd almost always touch him right on the end of his penis, even if he was wearing several layers of clothing.
Later, I wondered if she was trying to tell him something. He was diagnosed with bladder cancer in 2004, and died in November of that year...
