We've already seen that Akuma from Street Fighter is a guest character in, but Bandai Namco has informed us of two more guests from other games appearing in this title.
The DLC for Tekken 7 will be spread out fairly far apart. The first batch will be in Summer 2017 with a new game mode and over 50 new costumes. The second round of DLC will be in Winter 2017, including an exclusive guest character that has yet to be named. The second DLC guest character will be in Spring 2018.
These new guest characters will also come with their own stages and special costumes. To get all of these additions, a Season Pass will be available with even more costumes added in.
Tekken 7 will release June 2for PlayStation 4, Xbox One and PC.