The British fighter was knocked out by his countryman in the fifth round of their Wembley Stadium heavyweight title scrap at the weekend but the promoter thinks that a long-awaited bout against Fury is still possible for his charge.
Hearn told Sky Sports News: "My advice is don't do anything until December 21, Usyk vs Fury.
"If Tyson Fury loses that fight, you set up a big fight with Anthony Joshua. If Tyson Fury wins that fight, you make a voluntary defence against Anthony Joshua for the unified heavyweight championship.
"In AJ's mind, I think all he'll want to do is get back in with Daniel Dubois because they'll think they can beat him.
"In my mind, I think we have to wait to see what happens with Tyson Fury."
Hearn believes that the star power of both Joshua and Fury makes it an appealing fight for fans, even though neither fighter currently holds any of the world title belts.
He said: "If AJ is looking at a couple of big fights in 2025, and there is an opportunity to still fight Tyson Fury - because it's still the biggest fight in the division by a mile - I think that's something we should look at as well.
"Even in defeat, he's still the biggest star in Britain with Tyson Fury, and possibly around the world.
"He doesn't want to lose, but as we close the chapters to his career he'll be looking for the biggest fights."
Joshua was knocked down several times before the contest against Dubois was eventually stopped in the fifth round and Hearn acknowledged that his fighter had "made a lot of mistakes" in the ring.
The promoter said: "I think he made a lot of mistakes. Training camp went great and there are definitely no complaints from our side.
"He prepared really well, sparred excellently and on the night didn't do as he was told in terms of game plan. He let Dubois take the centre of the ring and be governor in there, and paid the price."