It may be that the soil used by the wholesaler was acidic, which resulted in blue blooms and the plant was then labeled/described as " a blue XYZ'.

A Hana Temani would have been listed/called/described as Hana Temani double light blue in that scenario, for example. But when the soil that the wolesaler uses is neutral or lacks aluminum, the blooms turn pink instead so the wholesaler would list/call/describe the same plant as Hana Temani double light pink.

Try www.heritagehydrangeas.com, they have a great online encyclopedia of hydrangeas with good info on the origin of all the best ones. You can check the names against their list of plant names to see all synonyms.

Here is a link that might be useful: Heritage Hydrangeas

Here are some pages which include beautiful photos of the same varieties I found. Mine are 1 and 3 in the first (blue) group and 11 in the second (pink) group. If you click on the image, a page for each variety opens. The variety name appears in roman script in the address bar of the browser. I still dont now how these plants came to be in my local garden centre, but I'm very pleased to have them! There are some stunning other hydrangeas on these pages, too.

Here is a link that might be useful: Hydrangeas in Japan

I forgot to mention, if you copy and paste the address into google as a search, you are offered 'google tanslation' versions of the site. It seems that Kamo Iris Gardens, Japan, has a hydrangea breeding programme and my local discoveries were raised there. It even explains that Temari-Temari was originally named Hana Temari, which was the label (mispelled Hana Temani) on one of my plants. The plant was re-named after its initial release. I think Hana Temari is possibly a registered name for a manga character!