While we have no idea if it will come out or not, in all likelihood the answer is probably no. Past instances of the remakes have only given us two games, never remaking the third game. The reason why is that the third entry in a generation provides minor upgrades over the previous games, but since the remakes come out later, they tend to provide all these upgrades and more. HGSS for example included the Suicune storyline elements of Crystal, Buena's Password, the expanded Ruins of Alph, the items given through phone calls, and the Extremespeed Dratini.
So it is very likely that ORAS will incorporate elements from Emerald version into the game, such as the Battle Frontier.
And touching on the fact that Pokemon Delta Emerald has been trademarked by Nintendo, this actually means nothing at all. It is common practice for companies to trademark products they have no intention of making in order to protect their copyright and prevent copyright infringement/the production of misleading products from others.
