Absolutely miniscule. Only Berwyn and Brint for men. Only Eryka for women.
Sandre, Kaerys, Meira, Kasyrra, etc are all moot, because they had a pussy from the start. So you don't swap their genitals, only take away their dick (temporarily in most cases).
A whole third of which are unsexable NPCs you only meet once in the entire game. Like that bunny girl wife of a minotaur dude, or this game's singular female goblin who we can't do anything with.
Curb your fact manipulation, and start counting real characters who player can interact with.
"Effigy Herald, Effigy Archer and how could I forget about Effigy Pollinator! Such great and memorable characters. Worth playing just for them."