In the My Hero Academia community, there is an idea that Tsuyu Asui/Froppy's Quirk is unsuited to hero work and doesn't compliment her strengths. That idea is inherently wrong. Tsuyu's Quirk is extremely versatile and makes great use of her creative thinking and flexible capabilities. On multiple occasions, her skills and Quirk have proven to be extremely helpful in dire situations.
During the villain invasion at USJ, she was able to save Izuku Midoriya easily when he was almost killed underwater by a villain. She got herself, Izuku and Mineta to safety in a situation when Class 1-A had no experience against villains. She also played a key role in passing her final exam when she and Fumikage Tokoyami were paired against their teacher, Ectoplasm.
Tsuyu's quirk is called "Frog" which enables her the same strengths and weaknesses as a frog. This includes extending her tongue to long distances, sticking to walls, increased flexibility, heightened swimming abilities, ejecting her stomach, etc. Her main weakness includes being vulnerable to cold temperatures. The colder the weather, the harder it is for her to function as she enters hibernation.
Quirk Bias in the My Hero Universe
In the My Hero Academia universe, characters are often judged based on their Quirks. Those with a flashier Quirk, like Katsuki Bakugou's Explosion, stand out and are often praised just based on their Quirk alone. On the other hand, the Quirkless, like Izuku, are looked down upon and seen as useless. Even Hitoshi Shinsou, whose brainwashing Quirk is a powerful asset, was disregarded due to his lack of combative abilities.
Tsuyu has a mutation-type Quirk, meaning that her abilities are a permanent part of her body. Nothing about her appearance is changed or activated when she is engaged in battle. As such, Tsuyu's Quirk does not stand out in comparison to some of her classmates. She often gets overlooked as attention shifts elsewhere.
Tsuyu wields her incredibly long tongue with great precision. It is used for long-range attacks, capturing opponents and saving comrades mid-air. The strength of her tongue is often seen to be lifting and restraining heavy objects and people proving that she can lift things that are several times her body weight. In addition to many other special abilities, her incredible flexibility is reminiscent of Spider-Man and makes her hard to catch.
Tsuyu has used her Quirk's lack of flashiness to increase her stealth tactics. Camouflage is a new ability that allows her to hide her presence to get in a sneak attack or to assist her comrades without being spotted, as seen in My Hero Academia: Two Heroes. Her secretion can have many effects and assists this super move by masking her scent. These are incredible tactics that her opponents should be wary of.
Tsuyu is Often Sidelined
My Hero Academia does not focus on Tsuyu much. Despite her versatile skill set, she is not seen in battle often in comparison to other characters. This is probably a result of the narrative trying to balance so many characters at once. Additionally, her character was not given the same kind of attention or training as someone like Fumikage or Shoto. It is known that Fumikage trained with Hawks to heighten his abilities and gain experience. The same can be said about Shoto training with Endeavor. However, Tsuyu never got that same level of training with a highly ranked pro hero. While she did train with Selkie during the internship arc in Season 2, that was in a filler episode.
Her Quirk isn't Slowing her Down
Tsuyu's Quirk is merely called Frog, with no specification as to what kind of frog her Quirk takes the form of. There are many different kinds of frogs all with their own unique abilities. Since Tsuyu's Quirk does not specify what kind of frog abilities she possesses, it's possible that she could gain more abilities from different frog species. During the exam, Recovery Girl mentioned that Tsuyu has no clear weaknesses thanks to her versatility. With her pre-existing skillset and intelligence, Tsuyu has great potential to be an extremely powerful character if given the proper screen time.
The reason Tsuyu doesn't get the spotlight is not at the fault of her Quirk, but because she is underused in the story. While her amazing capabilities are briefly shown, she is not given nearly enough time to show off her true prowess. That combined with the subtle uses of her Quirk in a world that praises flashiness and power over practicality makes it difficult for her to stand out. Nevertheless, Froppy fans can only be hopeful that she will get her time to shine as the story progresses.
