In fact, the updated version on DLsite also comes with a Flash version.
Among the following games, two that I have are Flash-only versions.
Game list:
あそんでおにいちゃん
おしえてほけんしつ
ふらふら-flafla-
にゃにゃにゃ!
ふらふら2 ~flafla-2~
世界の樹の下で迷う
にゃにゃにゃ2
王様の嫁と娘5
瞬足娘(flash only)
9娘
おにいちゃんわたしに○○○して(flash only)
怪談どうぶつえん...