The Congress can do that. The Constitution allows that:
Article III
Section 2 Paragraph 3:
The Trial of all Crimes, except in Cases of Impeachment, shall be by Jury; and such Trial shall be held in the State where the said Crimes shall have been committed; but when not committed within any State, the Trial shall be at such Place or Places as the Congress may by Law have directed.
“...but when not committed within any State, the Trial shall be at such Place or Places as the Congress may by Law have directed.”
Washington, DC is NOT A STATE......................
Congress can change the location for trials committed in DC if they want.