Wilder defends his WBC heavyweight championship against Fury on February 22 in Las Vegas before Joshua is expected to put his IBF, WBA and WBO belts at stake against Kubrat Pulev with the Tottenham Hotspur Stadium in pole position to host.
"Wilder said he has no interest in Joshua, and Joshua is irrelevant. That is baffling," Joshua's promoter Hearn told Sky Sports.
"That's why I want Fury to win because I know he's up for it! One phone call with me, [Fury's US-based promoter] Bob Arum and [Fury's management] MTK.
"AJ wants to fight Fury, Fury wants to fight AJ. It's a two-minute call with MTK and Bob Arum, done deal.
"But I'm not sure who will win [Wilder vs Fury 2]. The comments worry me that we're in the same position.
"The winner of that fight will be under so much pressure to fight Joshua that, this time, it will be unavoidable."
Wilder floored Fury twice in their first fight which ended in a draw 14 months ago. They have already spoken about fighting later in 2020, for a third time, regardless of the result later this month.
"The curveball is in terms of; those guys are preparing for their [third fight] and we have an opportunity in place that we can present to the winner to move them away from [a third fight]," Hearn explained.
"If the loser wants [a third fight] then we're tied."
Wilder appeared to distance himself from an undisputed world title fight after claiming that Joshua was "out of the picture" and branded the unified champion as a "coward".
The undefeated WBC champion also said about Fury surviving a nasty cut to outpoint Otto Wallin in his most recent fight: "I feel like the fight should have been stopped, with a cut so wide and deep. But I understand he had a major fight with me coming up. He was saved because of the fight that is happening right now.
"I'll be exploring the things that Wallin did. I look forward to re-cutting open his eye.
"Once it's open and blood is in his face, I might get some on me as well. That's alright. I'll embrace it. We'll see if they keep the fight on because I'm already dangerous.
"With that eye cut open again, and blood in his face, it's up to the doctors to take protocol. We already know my demeanour, my mannerisms, what I come to do. I don't play around at all."
Fury has replaced trainer Ben Davison with Sugarhill Steward since his draw with Wilder.
Wilder questioned: "I thought if it ain't broke don't fix it? If anybody should be changing things it should be me because he said that he beat me by a wide margin.
"It is nervous energy. He says he beat me but he doesn't honestly believe that. That's why he's changing things so much.
"He isn't confident dealing with me because of the state I left in him. The head is not meant to be hit by power like Deontay Wilder's.
"Deep down in his heart, I feel that he is very, very nervous. When you knock a person out and give them a concussion, you never forget that. You never forget who did it to you, and how they did it. When you go back in the ring with them a second time to relive it, it has to be stressful. You can't sleep at night."