An ActivityPub group actor defining its moderators is a specific implementation of the AP protocol. You can find the spec details lemmy uses here. An Mbin contributor recently implemented this to line up with Lemmy, but whether other fediverse software do or will is up to them, as it’s more of a community proposal than an official implementation of the spec. So when you see no moderators from other software, they likely just do not implement the linked FEP
An ActivityPub group actor defining its moderators is a specific implementation of the AP protocol. You can find the spec details lemmy uses here. An Mbin contributor recently implemented this to line up with Lemmy, but whether other fediverse software do or will is up to them, as it’s more of a community proposal than an official implementation of the spec. So when you see no moderators from other software, they likely just do not implement the linked FEP