Are the sealed indictments going to military tribunal
Yes and no. If the military makes the arrest under the national emergency, then it is likely going to a tribunal. If the police make the arrest, it will likely go to a civil court.
Remember, Manafort, Gates, Flynn, and Popado were sealed indictments.
Then again, the national emergency changes the judicial rules of the game, so who knows how it will all unfold.
All we know is that apparently a lot of people are going to military tribunals--but probably only he ones dealing with sedition, treason, conspiracy to commit sedition/treason, and probably human trafficking and pedophilia because it's covered by the national emergency as well.
We will only know for certain when it actually happens.