Iraq and Syria Genocide Relief and Accountability Act of 2018 This bill authorizes U.S. government agencies to provide humanitarian, stabilization, and recovery assistance for nationals and residents of Iraq and Syria, in particular ethnic and minority individuals at risk of persecution or war crimes. It also authorizes the agencies to assist in prosecuting those suspected of such crimes. (Sec. 5) The Department of State and the U.S. Agency for International Development (USAID) may provide financial and technical assistance to support entities, including nongovernmental organizations with expertise in international criminal investigations and law, to address crimes of genocide, crimes against humanity, or war crimes by the Islamic State of Iraq and Syria (ISIS) in Iraq. The assistance includes: conducting criminal investigations, developing indigenous investigative and judicial skills to adjudicate cases consistent with due process and respect for the rule of law, and collecting and preserving evidence for use in prosecutions. The State Department shall encourage foreign governments to identify and prosecute ISIS members suspected of committing such crimes. (Sec. 6) The State Department shall identify: threats of persecution, crimes against humanity, and war crimes against Iraqi or Syrian minority religious or ethnic groups; such groups that are at risk of forced migration and the primary reasons for such risk; humanitarian, stabilization, and recovery needs of these individuals; and entities, including faith-based entities, that are providing such assistance and the extent of U.S. assistance to or through such entities. The State Department and USAID may support entities that are providing aid to the vulnerable groups. (Sec. 7) The State Department shall report to Congress its efforts to implement this bill, as well as an assessment of the feasibility and advisability of prosecuting ISIS members.