I don't know if there's any tools that'll do that - I imagine it'd be an animation that you'd need to tediously build frame by frame. Gif is especially inefficient to simulate slowness because you need a new frame even when it's the same as the previous one, so the file would be massive. So you'd want to convert it to MP4 (which anything hosting it would probably do automatically) or use webp - this doesn't have particularly widespread support but it lets you create animations with a 'delay' element so you can hold certain frames. An example of that is here: https://lemmy.world/pictrs/image/218d951c-67b3-4589-ac94-8f661b32a8fc.webp (wait for it ...)
I'm guessing it's an artifact of them supporting both platforms like Lemmy (who's users make Threads and Comments in Magazines) and platforms like Mastodon (who's users make Posts and Replies in Microblogs).
If you don't like that, you're really not going to like what they call downvotes ...
Yeah - those individual Mastodon posts were tagged with @photography@a.gup.pe by their authors, and a.gup.pe picked up in the tag and made it part of the Group so PieFed could display it in a community.
a.gup.pe is a 3rd-party effort to wrangle individual Mastodon posts into Groups, so that Group-based fediverse platforms can follow them (a more familiar term for Group is 'community').
Doesn't look like it. There doesn't seem to be much of anything about discovering compatible things on other fediverse platforms (e.g. MBIN magazines, a.gup.pe groups, pixelfed groups [if they even exist], PeerTube channels, discourse / hubzilla whatevers, Flipboard thingies, etc).
For PeerTube, a good discovery tool is https://fedi.video, but that also involves tootling around on some other instance and copy/pasting handles back to your own platform, so it's not exactly that convenient.
It's partially fixable, by interacting with Mastodon the same way PeerTube does and have the community Announce only the posts. For everything else after that, it depends on whether the user is local or not. Anything a local user does could be sent directly, and if a remote user replied to a local user's post, the local user could send a 'post update', for Mastodon to then retrieve the replies collection, circumventing the problem of us not having the remote user's private keys. But if a remote user replied to a remote user's post on a local community, they'd be nothing we could do about it (don't have the keys for the 'post update', can't Announce it without it being spammy either)
Following communities from Mastodon works about as well as following Lemmy ones - this is something I'd like to improve, but it's only very recently that we got a community that wasn't a meta / testing one. Following users is less spammy, 'cos you'll get their posts, but not all their comments to other people's posts, so maybe you could try following someone like Rimu.
Either way, Mastodon doesn't process outboxes and backfill old stuff, so you'll have to wait for something new to be posted.
I don't know if there's any tools that'll do that - I imagine it'd be an animation that you'd need to tediously build frame by frame. Gif is especially inefficient to simulate slowness because you need a new frame even when it's the same as the previous one, so the file would be massive. So you'd want to convert it to MP4 (which anything hosting it would probably do automatically) or use webp - this doesn't have particularly widespread support but it lets you create animations with a 'delay' element so you can hold certain frames. An example of that is here: https://lemmy.world/pictrs/image/218d951c-67b3-4589-ac94-8f661b32a8fc.webp (wait for it ...)