I'm hesitant to reply because my more recent posts seem to have been taken out of context and seen in a negative light. About Rockette's words above, yes every server is a hodgepodge of diffierent cultures. I come from Alexander, we have players from India, Singapore, Indonesia, Hong Kong, Taiwan, Philippines, Russia (Vladivostok), Canada and Mexico, we stretch across many time zones and have large variances in culture too. It's hurtful that Rockette's words seem to imply that my earlier comments didn't take culture and time zones into consideration. However despite differences in culture and time zones, we are all fluent Japanese speakers, and we have an identity as members of Alexander server, Gaia DC. Personally I'm an ethnic Chinese Singaporean, fluent in English, Chinese, Indonesian, Japanese and German. My culture is significantly different from the Japanese (whatever similarities there are, the reasons behind it are different), I just happen to be fortunate enough to have to travel around a fair bit for my work. My intention was to share techniques used in my server and DC to handle certain problematic mechanics (e.g. acceleration bomb killing many players on a platform due to poor execution), so that if nothing else, they remember that one thing and maybe it saves their arsenal run. As I said, it was taken out of context, but this is the internet - people are free to interpret my words as they wish. After years of playing FFXIV, I decided to join the English forums to share since most information that NA/EU gets about JP servers is from Tonberry/Elemental and they don't seem to know much about Gaia or Mana, but I see now that it's my mistake and I should leave.
Sorry to digress, I'll answer your question. If you're talking about raids, we (Gaia data centre's Japanese speaking community, inclusive of the non-Japanese from many countries and time zones) generally have Pekolog's blog (http://pekoe1001.blog.shinobi.jp/) with detailed explanation for mechanics. Players convert them into macros. Other places we share:
(1) lodestone, probably the fastest place to get help and find strategies. It's the best thing since sliced bread for us. A lot of knowledge transmission is done here.
(2) twitter - us non-Japanese playing on JP servers, usually keep our twitter entirely in non-English as a platform to practice foreign languages, links to a new guide on Pekolog or someone's lodestone post are retweeted. Word gets around the community fast.
(3) ffxiv mobile companion app, LS members will remind us to check someone's twitter page for a retweet or that a certain website has been updated with guides for the latest content.
(4) Dopr.net's FFXIV guides, contains detailed information and guides on virtually all content in FFXIV to date ( https://www.dopr.net/ff14playguide ).
I'll include some examples of lodestone macro sharing below:
(i) Arsenal. (https://jp.finalfantasyxiv.com/lodes.../blog/4038064/)
(ii) Omega raid. (https://jp.finalfantasyxiv.com/lodes.../blog/3924606/)
(iii) Ultima weapon: Ultimate. (https://jp.finalfantasyxiv.com/lodes.../blog/3827052/)
I hope this is what you are looking for, and will help you.