Apparently not: [FIXED] Vacation Message / "Out of Office"-like system
“There’s now support for going into “Vacation Mode” and adding a comment/status to your avatar - for games that support turn timers (Civ 5/Beyond Earth) vacation mode will also automatically skip your turn while you’re in vacation mode.”
It’s something we used when we did PBEM for Civ 5 back in the day, so we assumed Civ 6 had it as well.