I'd heard of the band Buffalo Daughter during my days in Japan and I remember seeing one music video by them on one of the music channels on cable, but that was about the extent of my exposure. So, my knowledge of their music is still very limited although I had been under the impression that they were as Shibuya-kei as Pizzicato Five and Flipper's Guitar.
However, according to a Japan Times article via the Wikipedia write-up about Buffalo Daughter, member suGar Yoshinaga（シュガー吉永）has said that she doesn't really think the sound of the band has ever really been about Shibuya-kei. Judging from their snappy song "Oui Oui" from their 2014 album "Konjac-tion"（コニャクション）, I would tend to agree.
Although there is that vague feeling of French pop in "Oui Oui" which is a genre that has been one of the inspirations for Shibuya-kei back in the 1990s, I really see this song as being more of a pop/funk piece (and that's despite the Wikipedia categorization of their music all being various types of rock). Along with the funk beat, I also like the onomatopoeia in there, too.
Buffalo Daughter's other current members are Yumiko Ohno（大野由美子）and MoOoG Yamamoto（山本ムーグ）. They've been around since 1993 and have released six full studio albums. I will probably be playing catch-up with some of their past efforts.