Maybe, unless Marvel keeps their cameos a very huge secret until the film releases.

But why would Hugh and Tobey be secret if they each had their grand returns in phase 4 and 5 along with the original Kang dynasty plans @RJ Plotner

That's true, but at the moment it's very much a big rumor that they are returning. Same with whoever is available in the Marvel Multiverse.

It depends on the story and who will serve as the main characters

We will have to wait and see what happens after Doomsday to get a better understanding on what we can expect for Secret Wars

But it’s so obvious though that payoff why wouldn’t want to promote that lol

Again keep in mind that no matter what fans might say Tobey and Hugh aren't the main characters of this story, it still is and will always be the new Avengers.

You also don't won't to spoiled 2 of your biggest surprises in a trailer, it would be like if they spoiled Tobey or Andrew in No Way Home. it wouldn't make any sense. Save the Multiverse Characters for the actual film (and yes I am also including the other variants of Former MCU characters like Natasha, Tony, and even MCU 616/1999 Steve as well).

Lol says Kang dynasty written by ant man 3 writer and I think that the surprise cameos might mainly be animated spiderverse characters @IronWidowMaikuB