- Regular congregations
and
- Regular religious services
Just meet regularly. "Regular" is not defined, but monthly, or weekly would be good. You figure out what that means, but it does need to be predictable. That's less about legal stuff and more about the fact that you need some kind of predictable cadence for any type of organizing.
ULC says "Our ministers congregate online in the forums and in other places online. They meet regularly, as our forum is available 24/7."
Now, "congregations" and "services" can be different or they can overlap. People can "congregate" for services. A lot of anarchists would already qualify for both just by way of monthly general assemblies.
But services can also be different. You could, for example, regularly post some ideas to a specific mastodon account or to a specific hashtag as a "service" and then people can "congregate" on a specific server. That would, as far as I understand it, qualify.