He started his career in 1998 in the oil and gas sector in Nigeria where he was actively engaged in manpower planning, recruitment, selection and placement, industrial relations and human resource management policy issues. He later joined H. Pierson Consulting as as a human resource consultant and later became the Head of HR Consulting Business Unit of the firm. In this role he led the delivery of several human resource consulting projects in the areas of organizational restructuring, capacity building and capabilities development, process re-engineering and digitalization, competency models development, mergers and acquisition, as well as culture change initiatives for high level clients in the financial services, manufacturing, oil and gas as well as public sector.
In 2003 he joined Nestle, West and Central Africa where he successively rose to the position of HR Business Excellence Manager covering Nestle Companies in 23 countries of Central and West Africa. Among others, he was responsible for ensuring the design, delivery and alignment of the HR strategy to the business strategy in the various Nestle companies. He led the delivery of Performance Culture Projects - an initiative geared towards the optimization of the people management component of business performance and delivery. He was also responsible for setting up and nurturing the HR departments in various Nestle Companies in Central and West Africa including capacity building for HR staff in the Region. In this role he provided strategic leadership for the Industrial Relations work stream ensuring industrial harmony by creating structures and institutional policies and frameworks to drive conflict-competent work environments across the 23 Nestle Companies in the subregion.

Ezinwa subsequently joined the World Bank Group as Senior (Regional) HR Business Partner responsible for the delivery of end-to-end strategic HR advisory services and solutions to client staff, business leadership team, country directors and managers in World Bank Country offices in the Africa Region. Key responsibilities included leadership, team and organizational development, employee resourcing, compensation and benefits management, change management, employee engagement and work climate management, coaching, mentoring, performance management, talent management and organizational development and change management facilitation.