

You can’t on Lemmy, but can on mbin. I saw someone else mention just post, which will work for it, but I also just have a second account on a microblogging fedi platform for that, and that’s what I’d actually recommend for it. “You don’t need multiple accounts on the fediverse” yada yards, but there are certain instances where it’s helpful to have multiple, like this one xD
Diaspora isn’t, and I’m not sure if it has activity pub support at all? Most other things are. APub is turned on for Friendica (DFRN protocol) by default, and Hubzilla (Zot protocol) allows you to enable it pretty easily.
My line gets drawn based on what they’re made for. Friendica, Mastodon, GoToSocial, all of the *key forks, are all similar enough that I just have one account for all of them. They’re for microblogging.
Lemmy isn’t for microblogging, it’s a link aggregator/community forum-adjacent thing. It’s different enough in function that I want a different account/client for it, especially if we’re talking mastodon because Lemmy floods mastodon feeds.
If I cared about Bookwyrm, I’d have another account, same with PeerTube, etc. They feel different enough to the microblogs that I just prefer having accounts specific to them.