Mbewe made his senior international debut on 16 July 2016, starting in a 4-0 victory over Eswatini during qualifying for the African Nations Championship. Mbewe was named in the final squad for that tournament after Zambia qualified, appearing in all four matches against Uganda, Ivory Coast, Namibia, and Sudan. Mbewe was also included in Zambia's squad for the 2019 COSAFA Cup, appearing in all three of Zambia's matches as they won the tournament.