I know there is mobilzon but mobilzon is a meetup.com clone whereas evite is different.
Evite you can create an event and invite people via email or send them a link. They can rsvp and add it to their calendars.
Come of these features are covered by mobilzon but not quite. Evite doesn’t require you make a group or add people to the group as members. It’s a little more atomic. Honestly I think it’s a good deal more flexible than the meetup/mobilzon design pattern.
Very view fedi projects support event rsvp an the possibility to add events to the calendar. Hubzilla does and Streams and i think Friendica also…
Thought about that but it doesn’t seem to be active from what I can tell.
Maybe Gancio? https://gancio.org/
Why does it need to be a fediverse alternative, instead of icalendar/rfc-5545? Using activitypub for this sounds like a privacy nightmare.
