In the nation!! Not at 6'9". There aren't that many 6-9 women playing college ball this season. They probably will NOT face each other. They should ALWAYS be the tallest player on the floor. By now, they should know how to play the position, and take advantage of their height.
One of 3 things should/will happen...... 1. She goes up strong, makes the basket. 2. She goes up strong, makes the basket and gets fouled. 3. She puts her opposite number on the bench with foul trouble. As I said, Unless you're a leaper with lots of "hops", you're not going to out jump (or block her shot) 6-9!!
There's very little you can do against a player that's 3-4 inches taller than you. All you can do is hope you get some weak side help, and try and keep them from getting the ball. Once they get it in the paint, there's not a lot you can do.