Stef has been working on a big update for the online version for a while, and it will come out a couple weeks before Allies previews (week of Feb 28). It also includes all the new rules errata (such as the rules for playing cards, using coffers, and the new ruling for Star Chart). You can test it out here:
https://dev.dominion.games/Anyways, I can now give you the official wordings on *some* of the errata'd cards (not all of them; Hermit hasn't changed yet). I'm not going to cover the ones previously announced; if you need a refresher on Donate etc., go here:
http://forum.dominionstrategy.com/index.php?topic=20551.msg856350#msg856350.
Merchant Guild (Action):
+1 Buy
+$1
At the end of your Buy phase this turn, +1 Coffers per card you gained in it.
Note that there's no dividing line, and Merchant Guil cares about gaining, not buying.
Patron (Action):
+1 Villager
+$2
(dividing line)
When something causes you to reveal this in an Action phase (using the word "reveal"), +1 Coffers.
Citadel (Project):
The first time you play an Action card during each of your turns, replay it afterwards.
Prince (Action-Duration)
You may set aside (on this) a non-Duration Action card from your hand costing up to $4. At the start of each of your turns, play that card, leaving it set aside.
Surprise, Prince is getting the 2019 errata treatment. Note that it doesn't have the Command type, because that type only exists to avoid infinite loops. Also Prince is a now a permanent duration, like Hireling.