At international level, he features for Solomon Islands. His main role on the pitch is Defender. His estimated market valuation currently stands at 75K €.

His latest transfer saw him join Retired from Adelaide Cobras FC via on 2026-01-01.

Across the FIFA World Cup qualification (OFC) 2026, William Komasi appeared in 3 matches and averaged 0 tackles, 0 interceptions, 0 clearances, and 0 blocked shots per game.