Mass Effect 4 can likely only bring back a version of Shepard who made certain decisions in the original trilogy as well. The Mass Effect 4 trailer shows a dead Reaper, and BioWare's twitter account has posted concept art of Mass Relays being rebuilt.

Will there be a Mass Effect 4 with Shepard?

Mass Effect 4 looks like it's bringing back Commander Shepard, which will be a welcome return to many fans of the franchise. If not, BioWare will likely face questions over a moment in the upcoming game's trailer where fan-favorite companion Liara uncovers a piece of Shepard's N7 armor.

Is Shepard going to be in the new Mass Effect game?

BioWare is working on a new Mass Effect game alongside a new Dragon Age game. ... In other words, the protagonist of every Mass Effect game other than Mass Effect Andromeda. At the moment of writing this, BioWare and EA haven't said whether or not Shepard is returning with the new Mass Effect game.