I'm not sure if this could work with federation but personally I don't care much about favourites/like here... I'm not sure what's the benefit of knowing that a post has been "liked" by N people (in general, but specifically here).
One thing that came to mind is that when I see federated microblogging posts in the random magazine I wish I could "label" them to add them in a specific one so magazines could be curated by the community as well.
If something like this is possible maybe the "like" on the microblogging platform could mean that somebody put your post somewhere because it mattered, just like you can add any reaction on misskey/calckey and on mastodon it's just a like.
ScumbagSpruce