This is what I’ve been doing - The sidebar of the instance you want to save has a thing you can search like “!games@sh.itjust.works”

So you take your home server and plug in the instance like this: https://lemmy.world/c/games@sh.itjust.works

Then you should be able to subscribe. Probably a way easier way to do this or a script but this is what I’ve been doing so far.