Kuznetsova's 6-2 6-1 victory in Moscow ensured she took the eighth and final tournament spot.
Konta, who is in Singapore with the rest of the finalists, did not play this week due to an abdominal injury.
The Australian-born 25-year-old, ranked 10th in the world, will compete if any player withdraws.
Kuznetsova, 31, took just over an hour to defeat her 22-year-old Australian opponent on Saturday and qualify for her first WTA Finals since 2009.
"I was trying not to think about Singapore all week. I was playing match by match and I'm so happy to win," she said.
Kuznetsova will next face world number three Agnieszka Radwanska of Poland in Monday's group stages, before later games against Czech Karolina Pliskova and Garbine Muguruza of Spain.
Konta will finish her season at the WTA Elite Trophy for players ranked from ninth to 20th, which gets under way in Zuhai, China, on 1 November.
It will complete a season that has seen her named the most improved player of the year after she recorded seven victories over top-10 players, and became the first British woman to break into the top 10 since Jo Durie in 1984.
British number one Johanna Konta missed out on a place in the WTA Finals after Russia's Svetlana Kuznetsova beat Daria Gavrilova in the Kremlin Cup.