I don't know if this is helpful or not, but you can do this on Sync for Lemmy. As a test, I just added you as a favourite and now you appear in my Favs list alongside my chosen top communities.

However I don't know if there's any way to create a feed consisting of all favourited people's posts, which would be more useful IMO than having to check each individual favourited person. Will have a go and see if I can find a way.

EDIT: Couldn't see a way to do it unfortunately, but have started a thread on the Sync community to see if anyone knows how.

It could be nice.
In the meantime, since I use lemmy in a browser, bookmarks work OK for this purpose.

I know that Thunder lets you "label" users so you can recongize them more easily, and I think you can find a list of labeled users somewhere in the app, too.