Is Free! Movie 4: The Final Stroke - Zenpen hentai?
English title: Free! the Final Stroke: The First Volume
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Movie · 2021 · 1 episodes · PG-13 - Teens 13 or older
School, Sports
Haruka Nanase's new stage is Sydney, the place of his dreams that he once visited. One day while taking a short break before his departure, Haru has a chance confrontation with a fellow athlete from the All-Japan Invitational. Carrying all the feelings from those he's swam with in his heart, Haru takes his first step forward into a new world. Waiting for him there is the unmistakable champion, Albert Volandel. In the lead up to the Sydney tournament, all the competitors attempt to boost their morale. What is each competitor feeling, and what do they swim for, as they attempt to compete at the top of the world? Their passionate struggle against the water begins from here――! (Source: Free! website, Translated)
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