African Growth and Opportunity Act and Millennium Challenge Act Modernization Act or the AGOA and MCA Modernization Act This bill directs the President to establish a website for the collection and dissemination of information regarding the African Growth and Opportunity Act (AGOA). The Department of State is urged to encourage eligible sub-Saharan African countries to use AGOA benefits. The President is urged to: facilitate trans-boundary trade among eligible sub-Saharan African countries; provide AGOA benefits training for business and government trade officials; provide capacity building for African entrepreneurs and trade associations on production strategies, quality standards, and market development; and provide capacity building training. The Millennium Challenge Act of 2003 is amended to permit an eligible country that has entered into a Millennium Challenge Compact to enter into one additional compact. The bill establishes new assistance criteria for a low-income or a lower-middle-income candidate country to enter into a compact with the United States. The Millennium Challenge Corporation shall: (1) before selecting a compact country, provide the Board of Directors with information regarding the country's treatment of civil society; and (2) assess the feasibility of developing subnational partnerships.