Been using for what feels like a lifetime, although I went through a few usernames during the late 90s early 00s and somewhere along the way BlueEther or a derivative just stuck, it was after a comment something like “jus putting this out into the blue ether” in a forum post
The correct way (for your use case) is probably to do a full backup of the database and pictrs database and then import them into the new instance.
This is covered in the documentation