You can consider some major festivals in Japan like Tsukimi (Mid-Autumn), Kishiwada Danjiri Matsuri, Shiretoko Shari Neputa Matsuri, Akimatsuri, etc. Since each festival is held in different places, let's make sure to double-check. I don't remember clearly, but I recommend Tsukimi and Kishiwada Danjiri Matsuri festivals. They are quite enjoyable.
Japan boasts numerous festivals. Examples include cherry blossom festivals (hanami), Gion Matsuri in Kyoto, Tanabata, and the Nebuta Festival in Aomori, known for its vibrant illuminated floats.