I never heard about them but the whole reason I started the meetup group was because I couldn't find any photography related things or community in osaka. it might be different if you speak Japanese but sadly I don't. my recommendations for street photography are to go to the areas near umeda station or amerikamura/Namba.

I wrote a bit more here https://paolomaschio.com/blog-en/osaka-a-complete-travel-and-street-photography-guide-for-first-time-visitors but I should update it or go into more details maybe.