Department of Homeland Security Rotational Cybersecurity Program Act of 2019 or the DHS Rotational Cybersecurity Program Act of 2019 This bill authorizes the Department of Homeland Security (DHS) to establish a rotational cybersecurity research, development, and training program. Under such program, DHS shall detail to the Cybersecurity and Infrastructure Security Agency (CISA) (including the national cybersecurity and communications integration center) Coast Guard Academy graduates and faculty. DHS shall detail to the Coast Guard Academy, as faculty, individuals with expertise and experience in cybersecurity who are employed by (1) CISA; (2) the Directorate of Science and Technology; or (3) institutions that have been designated by DHS as a Center of Excellence for Cyber Defense, or the equivalent.