Or is it faster to do it manually? I am subscribed to almost 120 different communities, so would save a few clicks not having to do it manually.
Export/Import can be found in your profile settings
This tool exists on github.com to do just that. Not sure if it works with ver 0.19 though, it is a few months old.
There’s an assumption in the comments that this is Lemmy-specific, so I figured I should also mention a tool I used recently when copying subscriptions from a kbin instance to an mbin instance.
I’m using this Python-based tool.