I tried to decipher the naming themes:

Festivals:

    - Tsuzumi = drum used in festivals
    - Taiko = drum used in festivals
    - Happi = clothes worn in festivals
    - Wasshoi = shout used in festivals
    - Hanabi = fireworks
    - Matsuri = festival
    - Chouchin = latern used in festivals
    - Bonbori = type of light used in hina festival

Food:

    - Monaka = bean paste filled snack
    - Ichigo = strawberry
    - Basil = culinary plant
    - Momoha = maybe derived from momonoha, which is a culinary plant
    - Peach = fruit
    - Akebi = fruit
    - Omochi = snack
    - Chanko = hot pot
    - Fuji = apple
    - Melon = fruit
    - Ohagi = snack
    - Sour = flavor
    - Yuzu = fruit
    - Ponzu sauce
    - Ramune = drink
    - Warabi = type of mochi
    - Yomogi = type of mochi
    - Daifuku = snack
    - Cookie = cookie
    - Ringo = apple
    - Potechi = potato chips
    - Cherry = fruit
    - Lime = fruit
    - Marron = chestnut
    - Kinako = soybean flour
    - Banana = fruit
    - Zunda = paste made from edamame
    - Suika = watermelon
    - Shiratama = snack
    - Cocoa = cocoa
    - Ame = candy
    - Choco = chocolate
    - Arare = snack
    - Anmitsu = bean paste snack
    - Anko = bean paste
    - Anzu = fruit
    - Macaron = snack
    - Koume = plum

Plants:

    - Pine = tree
    - Momiji = maple
    - Susuki = tree
    - Rose = flower
    - Tsumugi = flower
    - Nadeshiko = flower
    - Sakura = flower
    - Komari = flower
    - Aloe = plant
    - Ajisai = flower
    - Kiriko = flower
    - Azuma = plant

The names were collected roughly left to right. I was reading the Japanese version[1] so some of the romanizations might not match the English version.

[1] https://www.sumida-aquarium.com/special/sokanzu/

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