Mirrorrorrim
Hero
I have a very simple Uncommon magic item solution that I've already planned. When my players build their Bastion, one of the things they can do is acquire/create a pair of Sending Stones that your "major domo/seneschal" has the twin to.Still that wording that a character can like psychically rule their Bastion is just weird.
Perfect for long distance "orders" that are forced to be short and to the point, so you can be efficient and not bogged down by pleasantries.
I also have a magic item in my campaign that is a pair of magically-connected Journals that two people can use to communicate via writing.