Emergency Medical Manufacturing Library Act of 2020 This bill directs the Federal Emergency Management Agency (FEMA) to coordinate the development of plans, designs, and guidance relating to the production of certain homeland security-critical supplies to address potential national emergencies and disasters. Specifically, FEMA shall coordinate with other relevant federal departments and agencies to identify categories of homeland security-critical supplies that would be needed to address potential national emergencies or disasters, including any such public health emergency, terrorist incident, armed attack, or cyber attack; to develop plans, designs, and guidance relating to the production of the categories of homeland security-critical supplies identified to address the respective national emergencies and disasters, including such production by nontraditional manufacturers; and based on such final plans, designs, and guidance, to enter into such contingent arrangements with governmental and private entities to expedite the production of homeland security-critical supplies in the event of a national emergency or disaster. FEMA shall (1) publish each final plan, design, or guidance that is developed on a public website, except for protected information; and (2) at least every two years, coordinate the review and revision of each plan, design, and guidance in effect.