These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Fridge Brilliance: Throughout the film, Viola was consistently looked down and denied opportunity to play soccer, simply because she was a girl. But at the end, when Duke lifted her up, she became "higher" than those who put her down.
Fridge Logic: Viola can kick a ball through a life buoy from a respectable distance, and is said to be better than half the guys (admittedly by her boyfriend while flirting). Yet she doesn't make the Illyria team initially. This would ordinarily imply that the Illyria is much better than the Corwall team, but in the final match, they are almost equal.
I think her disguise was giving her issues.
When Viola confesses, she takes of her sideburns, eyebrows and wig. She now looks like she did at the kissing booth. She also just recovered her skills being temporarily terrible. Yet Duke thinks she may still be male. So she has to flash.