水まんじゅう mizu manjuu literally translates to “water dumpling.” Sometimes they are also called “kuzu manjuu” くずまんじゅう.
Mizu manjuu are a popular summer time treat because they are served chilled. The outside is made from kuzu starch (arrowroot 葛) which gives it the translucent effect. The inside filling which you can see through the outer layer is either azuki paste or a fruit-jelly paste with white bean. The taste is so refreshing, perfect to balance the hot summer days. And the outer appearance is so cute and delicate.
The ones in my first picture are matcha 抹茶 and raspberry ラズベリー. The second picture is shikwasa シークワーサー flavor. The third picture is a really creamy and tangy sour cream flavor, no bean paste used.
In Okinawa, you can find these at Shirobara confectionary (白バラ洋菓子) which has a few locations throughout Okinawan main island. Just copy and paste into Google Maps to find the closest to you. I have also seen a few at SanA grocery store during summer.