The Enma cloud was due to Zoro incomplete mastery over Enma to show us it was draining him by taking too much haki that seems to be gone now since he came down against King as you can see in this panel
If this cloud was special ability of Enma don't you think we would have seen this with Oden it's original user
He clashed with WB using hardening, cut that boar in half with haki still we didn't see any cloud around it. When he faced Kaido and scarred Kaido it's the same thing not to mention Ame did just as much damage, there is no reason to believe Zoro will be relying on this sword more than his 2 others