Two weeks ago I scraped 2ch.hk/fag/ OP posts from "arhivach" archive. You can grep the directory or use VSCodium as a makeshift search, it's only 110 MB unzipped.
From what I understand, this board is similar to whatever guys you do here, on /agatha/: e-celebs discussion, pics and "drama". There's another board on Russian 2ch, /fd/ - Fandoms, and it seems to be a mix of /cgl/ and /lolcow/, geared to discussing solely professional "e-celebs", e.g. cosplayers and softcore e-whores who position themselves as cosplayers, the audience seems to be different as well, mostly women saying mean things about these cosplayers.
Since the archive site is on-demand, not every thread is saved, and there's not much garbage, only what some person decided was worth saving. The site itself seems rather unstable and struggles with keeping domain names due to questionable content it accumulates, currently they are located here:
https://arhivach.top/
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/
Old defunct domain names some of them in still in Yandex search caches (use
site:website.tld operator):
http://arhivach.org
http://arhivach.cf
http://arhivach.net
http://arhivach.ng
http://arhivachovtj2jrp.onion which could have been indexed by any search engine through one of those tor2web gateways back when v2 onion sites still worked (or ended up on archive.is which does visit onion sites)
https://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion.darknet2web.info is the current gateway they recommend, searchable through Yandex.
The archive has a decent tagging system, most recent threads would have some tag besides automatic ones denoting board and site of each thread, but this is why I did the scrape: very rare Elizas from early 2017 are not searchable and untagged.
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/thread/227815/
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/thread/232461/
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/thread/481705/
A rare Marky thread I found through google images which sent me here first:
https://2ch.hk/b/arch/2018-07-23/res/180006136.html
Then using some webshit woodoo majick I go to
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/ajax/?act=locate_thread&url=https://2ch.hk/b/res/180006136.html
Which redirects me to final destination if the thread is archived
http://arhivachqqqvwqcotafhk4ks2he56seuwcshpayrm5myeq45vlff44yd.onion/thread/376177/
Besides, there's another 2ch archive which mirrors every thread, but only posts and thumbnails:
https://m2ch.hk/