Rumors say that there is another next-gen Xbox console in the works right now and being developed by Microsoft.
Aside from the Xbox Series S and X, this new rumor on a Twitter post says that there will be a third next-gen Xbox console in the near future. According to @IdleSloth84, the rumor claimed that the third one is called Xbox Series V (Not E) and is now under development currently under the working title of Project Edinburg.
Aside from the name and its project name designation, the rumor said that the specifications for this new next-gen Xbox console will be a little bit less powerful than the Xbox Series X. It also said that it will be more powerful than the Xbox Series S. There was also an image attached to it and it surprisingly almost looks like the Xbox Series X in color and size.
Again, this is just a rumor and has not been confirmed by Microsoft right now. Take this new rumor with a grain of salt.