I don't know, but you could start one if there isn't! It's as easy as tagging '[name] @ [a.gup.pe]' in a post. The group is automatically created and will automatically boost any message that it's tagged in! Groups are super easy =)
[@FediTips](https://social.growyourown.services/@FediTips ) has a great post on it here: https://fedi.tips/how-to-use-groups-on-the-fediverse/