YahooGroups Shutdown

In hopes this will be helpful, I've made a list of alternatives for YahooGroups. I'm making a new post instead of a comment so as to TRY to reduce the overload on morgandawn

Groups.io
Only viable option for transfer, but Adult Content not permitted.
Easy import of YahooGroups, but requires Premium Membership for one year $110 $220. https://groups.io/static/pricing
For some reason, they require login to view the process, so I'm pasting it here:

( Groups.io Transfer )

Squidge
Has email list servers and archives, but archives appear to be publicly readable instead of password locked to members. Adult content/fan friendly. Dated look, but also hosts pages and files. Probably the closest match to replacing YahooGroups.
https://www.squidge.org/

Dreamwidth
Adult content/fan friendly. It allows explicit material, is free, has threaded conversations, privacy locks and more. Image uploading is limited to 500MB free accounts and 1.5GB paid accounts. Can be set to email comments on your post and replies to your comments, but not primarily an email server.
https://dreamwidth.org

Google Groups
Adult Content not permitted.
May be impossible to transfer. If possible, it's way complicated for those of us who don't write computer code for a living.
https://stackoverflow.com/questions/35966337/transition-from-yahoo-groups-to-google-groups
https://support.google.com/a/thread/17075653?hl=en
https://support.google.com/a/thread/16986960?hl=en

Mobilize.io
Does not appear to have a way to import Yahoo Groups. Unknown position on adult material.
Looks like it has the necessary features, including a free level that handles most of what fan-based groups would need. Includes a mobile app. Geared toward businesses and techies, though. Not a lot of info on what I was trying to find out on their site, and the "ask" link wants name, title, company, email, and phone for someone to contact you back later.
https://www.mobilize.io/pricing
https://www.youtube.com/watch?v=pYoIzl6o8E8

Slack.com
Does not appear to have a way to import Yahoo Groups. Unknown position on adult material.
Not sure which came first, but it looks a lot like Mobilize.io. Free plan only allows access to the most recent 10,000 messages, though.
https://slack.com/pricing/free
https://www.youtube.com/watch?v=6c7_TpPUpL0

Wordpress Plugin
Requires your own hosted Wordpress installation, not WordPress.com.
Moderation, archiving messages, and importing members requires premium version, but unhappy reviewer says it's clunky at best. No mention of whether import includes messages and files, but given the member import apparently is limited to batches of 10, I'd say probably not.
https://wordpress.org/plugins/wp-mailing-group/

GroupSpaces
Does not appear to have a way to import YahooGroups. Unknown position on adult material.
Appears to be all of Yahoogroups functionality plus some, but Free is limited to only 50 members.
http://groupspaces.com/pricing

Zoho
Does not appear to have a way to import YahooGroups. Unknown position on adult material.
The sheer number of apps available is daunting, but Cliq appears to be their closest match to YahooGroups.
https://www.zoho.com/cliq/pricing.html
They also have something called Connect, but the free plan is limited to 25 members.
https://www.zoho.com/connect/pricing.html

Basecamp
Does not appear to have a way to import YahooGroups. Unknown position on adult material.
Doesn't seem to do email at all - instead focused on message boards, chat, online task lists, calendar/scheduling. Does have file storage. The free version is limited to 20 members.
https://basecamp.com/pricing

Wikipedia has a list of some mailing list software, which will require hosting/servers and technical know-how:
https://en.wikipedia.org/wiki/List_of_mailing_list_software

Filehosting and sharing is another whole book's worth of discussion, but if the group itself can't move to a provider that offers all the same pieces that YahooGroups had, it is possible to split the services up to separate providers, if necessary.

Extended Rambling about Calibre and FanFicFare

Couldn't figure out a synonym for post that started with F, sorry.

I started with FanfictionDownloader, too, which made nicer HTML files, IMO, but FFF is so much more powerful.

If having separate directories is the issue, please be aware that Calibre will let you make as many separate Library directories as you want. I have Food/Gardening, (other) Nonfiction, (commercial) Fiction, Fanfiction (that I've read and liked), (unread fanfic) To Sort In Progress, To Sort Long, To Sort Short, To Sort Series, and a fileless Physical Fiction Library. I have yet to find a limit on how many libraries I can have.

Also, Calibre will make lots of custom columns for useful sorting, and has the option of custom coloring the text based on your filter criteria. A lot of what you have on your database is the kind of thing I've been trying to figure the best way to share, though it looks like we don't have any overlapping fandoms.

Calibre's catalog function will create the spreadsheets. I've looked into shared Calibre libraries (looks like you can't make it read-only and public, though, which defeats my purpose) and so far, the best option I've found is a dynamic table:
https://datatables.net/forums/discussion/1632/import-csv-into-datatable

Of course, I haven't done it yet, because I've been too distracted trying to make a dent in my oversized To Sort libraries. You want to try collaborating on this? I've been making do with marking my favorites on FFN and AO3 instead.

Oh, and since AO3 is out of control with the tags, I've completely abandoned the tagging function on my Calibre libraries. It's too much to try to clean up, so I just pretend they aren't there. On the other hand, it sounds like tagging will do exactly what you want, so you'll want to ride herd on the tags you download with the stories.

I found it a lot easier to just download most of the stories again, even though I had a lot of them downloaded with FFDL before. Obviously the deleted ones won't work that way, but manually entering the metadata is annoyingly time-consuming.

You'll want to avoid downloading too many at a time, to avoid getting server-banned. Usually 5-10 is okay, but it can vary.