the user https://sh.itjust.works/u/goat appears to be impersonating the mastodon user https://hellsite.site/@goat
same profile picture, name, however the sh.itjust.works user has decided to create a hate community, https://sh.itjust.works/c/meanwhileongrad as well as spreading misinformation about the lemmy developers.
I would normally just block and move on but I find it dangerous to allow someone to impersonate someone else on the fediverse (an admin too) and begin starting trouble.
I’m gonna ignore the political stuff and actually answer your question: impersonation is a shit thing to do no matter who the target is, but there’s no centralized authority or terms of service in the fediverse. That’s kinda the whole point of it.
The above user is on mastodon, so they can verify their identity there by adding a line of code to their web site and then linking to their web site on masto. Instructions here: https://barrd.dev/article/add-a-verified-website-to-your-mastodon-account/
Once they’ve done that, they can pin a toot saying only to trust this account and no others.
If they don’t have a web site, welp. Never too late to make one.