Interesting analogy with Phantom. It gives me an idea of what a teaser trailer would look like:
Begin with the wide establishing shot of a performance stage. Like something modern, like from the Idol show. The theatre is dead quiet, and a long female figure walks into the spotlight to a lone microphone on a stand.
We close up on the female, who is clearly Asian, and she approaches the microphone and opens her lips. She begins singing an a capella (voice only) soft pop ballad, maybe in English but not necessarily. We pan out to the audience, full of general people held in rapt, silent attention. We notice some of them are wearing unusual clothes, as if from the future.
Cut to what appears to be a crowded outdoor public space, like Times Square. People are standing, listening and watching the singer, who will continue to sing throughout the trailer, via large public TV screens. More futuristic people, but we also notice a lot of men and women in what appear to be military uniforms. Zoom out further, and we see the public square flanked by 3-4 giant humanoid robots (what???). We pan to the sky, and see the blackness of space beneath what appears to be a clear dome.
Zoom out further (the singer is still singing) and we find we are looking at a clear dome aboard what appears to be a giant battleship in space. Suddenly, what appears to be a fighter jet flies across the screen, but transforms into one of the humanoid robots, pauses for a second, then flies at the camera.
Cut to black. Cue the text:
Robotech. Summer 2018.