They are wearing kimono. The garments are all clearly lined (the lining is visible at the hem). The two at either ends are wearing kimono lined in yellow, the girl in grey has a lining of light blue, and the other girl has a lining of red and a white under-kimono. These are in fact wearing polyester kimono, hanhaba obi, and haori that I am very certain came from a rental shop.
It is very common in Kyoto to see women in kimono, but in reality the majority of them are in rental kimono that they did not put on themselves. Many rental services have cheap ensemble sets (cheap because they are polyester) that come with dressing services and sometimes hair and make-up. These services cater to both locals and tourists (domestic and foreign) so that people can go to shrines and temples, a day at the theater, or a restaurant in Gion Koubu while feeling traditional. It's easy to spot these ladies because, one, their kimono are all styled in a late Taisho/early Showa revival style (which is fashionable right now), and, two, because they tend to be wearing the same ones so there are a bunch of pictures of different ladies wearing the exact same ensembles. Also, the styling of the hanhaba bow is rather professional, not the sort of thing the average person knows how to do.
Fascinating! I love how you know about kimonos and the culture surrounding them. I will say, I find it kind of funny that they have professionally tied obi but they're carrying cheap collapsible umbrellas. Anyway, thank you again for the insightful comment!