Lets say I want to ask Lemmitors a question. There might an AskLemmy community at my home server so I can ask there. But there might be a much larger AskLemmy community on a server elsewhere. Is there a way to ensure that people who subscribe to AskLemmy on the other server could also see my post on AskLemmy on my home server ?
That's not really how I interpreted the question. I think he just wants to show all the "ask lemmy" communities in one shared feed. You could even have posts that link to the same link collapse together, like tabs for which instance's comments you're reading.
That would be neat and would make Lemmy feel much larger. And it would all be in the client end right?