Scene begins when Sonic gets defeated by Infinite just like in the Sonic Forces first cutscene.
Sonic: "It's no use. But how could I lose to you?"
Eggman: "Because... we are Eggman Heroes!"
Eggman, Infinite, Shadow, Zavoc, Chaos and Metal make the Sonic Heroes pose. Eggman in place of Sonic. Not all of the other 5 characters need to be there necessarily, but perhaps Infinite should be there.
Sonic: "But... you don't have friends..."
Eggman: "I didn't. But it's you who taught me this lesson. Each time you defeated me, you gave me a lecture!"
Flashback to various past events when Sonic had beaten Eggman and was gloating about it. He gets progressively more preachy and acts more like a bully:
Sonic: "We are Sonic Heroes!"
Sonic: "The power of friendship overcomes all obstacles!"
Sonic: "The heart, soul and bonds of friendship are more powerful than strength in numbers!"
Sonic: "I have friends and you do-on't!"
Sonic: "Look at him! Look how lonely