Stadistically the swimmer has the most chances to place a gold as she is allowed to participate in 17 different categories. And she is also a diver so thats 4 more categories. So she has the most chances to place on a podium
Actually seems like Japan dominates Judo, but its just one event determined by your weight and a new mixed event so is do or die for her.
Japan does well on gymnasts and she has 6 categories + 2 on trampoline and most gymnasts do all categories, but gymnasts have the shortest active life so these might as well be her only shot.
Tennis has singles, doubles and mixed and japan has never done well on them.
Btw the flashforward shows a team so realistically it could only be the swimmer or the gymnast. In artistic gymnastics all aparatus on teams is the big category so it even fits.
But of course is the other girls.