In March 2016, Pokomela was included in a South Africa Under-20 training squad, and made the cut to be named in a reduced provisional squad a week later. On 10 May 2016, he was included in the final squad for the 2016 World Rugby Under 20 Championship tournament to be held in Manchester, England, also being named vice-captain of the team. He started in their opening match in Pool C of the tournament as South Africa came from behind to beat Japan 59–19. He also started their other two pool matches as South Africa were beaten 13–19 by Argentina in their second match, but bounced back to secure a 40-31 bonus-point victory over France in their final pool match to secure a semi-final place as the best runner-up in the competition. He retained his starting spot in the play-offs, as South Africa faced three-time champions England in the semi-finals, but the hosts proved too strong for South Africa, knocking them out of the competition with a 39–17 victory. Following captain Jeremy Ward being handed a two-week ban for a dangerous tackle against England, Pokomela captained the side against Argentina in the third-place play-off final. Argentina beat South Africa – as they did in the pool stages – convincingly winning 49–19 and in the process condemning South Africa to fourth place in the competition.