VA Clinician Appreciation, Recruitment, Education, Expansion, and Retention Support (CAREERS) Act of 2023 This bill addresses Department of Veterans Affairs (VA) personnel matters and the training, recruitment, and retention of VA health care employees. Among other requirements, the VA must expand various staff training efforts and programs; comply with certain notification and staffing requirements when a VA medical center director is on detail; prescribe a system of pay for individuals appointed as directors of medical centers and directors of Veterans Integrated Service Networks; and establish a consolidated annual leave account for certain VA employees with restored leave during 2020, 2021, and 2022. The bill also authorizes the VA to waive pay limitations for employees of the Veterans Health Administration (VHA) who are performing mission critical work; increases the maximum amount of incentive pay for pharmacist executives; modifies the special pay authority for nurse executives and the administration of pay for VA physicians, podiatrists, optometrists, and dentists; authorizes a waiver of certain licensure requirements for psychologists and mental health counselors in certain circumstances; requires the Inspector General of the VA to study and report on the use of direct hire authority, the contributions made by the use of such authority, and any vulnerabilities or inconsistencies with respect to the use of such authority; includes VA police officers as law enforcement officers for purposes of the federal retirement system; and requires the Government Accountability Office to report on human resources modernization conducted by the VHA.