I didn’t mean federate in the Lemmy/Fediverse sense, but rather in the collation/multireddit sense. In other words, gathering posts from many different sources, in this case instances, and displaying them as a single list. Given the context, calling this “federation” was probably very confusing, and definitely a poor choice of words. I apologize for that.

In Liftoff, this takes the form of an All/Everything view (where “All” means all currently logged in instances) which collates and displays posts from many different Lemmy instances at once. This is the feature I was looking for in other clients.

In this context it probably is, since the federation that is done on the fediverse is something else entirely. “Collate” might be a better word, perhaps.

Workaround