Family First Transition and Support Act of 2019 This bill eliminates income-based limitations on a child's eligibility for federal foster care support and makes other changes to funding for, and administration of, grants and programs for child welfare in states and tribes. The bill increases funding for activities including (1) training of child welfare workers, foster parents, and those working in the court system; (2) research on evidence-based practices to prevent child abuse and neglect; and (3) regional partnerships between child welfare agencies and others to address a parent's, or other caregiver's, substance use disorder. The bill's changes to the administration of child welfare programs include, for example, delaying until FY2027 a requirement for states to expend a minimum percentage of funding for child abuse prevention services on only those services that meet certain criteria for effectiveness. In addition, the bill expands the scope of certain grants to include kinship placement services and allows the use of federal funds to address issues that may put a child at risk of entering foster care, such as by providing assistance with housing and utility payments.