If you’re one of us freeloaders and got Civilizazion VI at Epic Games’ free game giveaway, you might have had the same problems we had to get the bloody thing running multiplayer. Internet play is desync hell, cloud didn’t work at all and hotseat is… well, annoying. And created LAN games just didn’t show up on the other person’s radar.
After trying all the usual LAN solutions and several well-meaning Civ-specific solutions, we managed to get it working. The secret was friending your LAN partners in the Epic Games launcher, which a weird prerequisite for a LAN game, but there you are. We also signed up for 2K Games accounts beforehand, but that alone did nothing. Can’t say whether it helped in the end, though. So try it if you’re stuck after friending.