Gog.com contributing to the CoronaVirus out of things to do with a list of 20+ games that are currently being offered for free. Its Gog, so mostly these are older lesser known games but there are a couple Ultima games on the list, Shadow Warrior Classic, Postal, and at least one game Legend of Keepers that just came out today and has a free prologue-its got some elements of Darkest Dungeon and Slay the Spire in it:
https://www.gog.com/partner/stay_at_home