Short of basically showing the NX, they really can't at this point.
Final Fantasy VII isn't just a big game, it really is even to this day perhaps THE defining game of the Playstation brand, that was a long time in coming and rumored for so long ... it's just one of those things. Even a new Zelda wouldn't have the same impact, we've had many new Zelda games, but FF7 Remake is something people have waited for almost 20 years for.
Doesn't mean however Nintendo won't have a good show in a few hours. Nintendo's new format totally is far better than the Sony/MS way of doing things too so that helps.










