Heartwarming / Little Witch Academia: The Exchange

• As awesome was Sucy's What the Hell, Hero? was, it clearly shows that Sucy cared more about Akko than she let on. Diana might be helping, but saying that she was Akko's friend was a real Berserk Button for Sucy, who never had quite forgiven Diana for the Pappiliodya incident.
• Akko meets past Croix. Despite it being a rough start, Akko praising Croix's future accomplishments really touched her, as she realized that she would accomplish something worthwhile after all.
• When Ursula forbade Chariot from seeing Croix ever again, Chariot was outraged and called out Ursula for merely thinking it.
• Although it was brief, Akko smiling at seeing a younger Diana being happy to see magic. Then Bernadette appears, showing that Diana was at her happiest when she still had her mother.
• Past!Croix apologizing to Akko for creating Dream Fuel Spirit. Before the series, Croix did have the capacity for compassion, just as the memories of Chariot showed.
• Diana saving Akko from making what would be the worst mistake of her life.
• It was a long journey, but Akko finally gets to meet her idol.
• Chariot and Croix making amends.
• In the Epilogue, we see Akko and Diana as friends. Akko's actions in the past and Chariot's experience in the future ultimately change history. Chariot and Croix succeed in restoring the Grand Triskellion, thus Chariot never needed to go into hiding. What's even sweeter is that, due to being inspired by the time-travelling Akko in the past, Diana goes against the expectations of everyone else to tutor the Akko of her timeline. This, combined with the fact that her potential was never sapped away by DFS, results in Akko becoming quite decent at magic in a short amount of time.