[6] In July 2018, Waiswa was part of Uganda's squad in the Eastern sub-region group for the 2018–19 ICC World Twenty20 Africa Qualifier tournament.
[10] The following month, he was named in Uganda's squad for the 2018 ICC World Cricket League Division Three tournament in Oman.
[11] In July 2019, he was among the 25 players included in the Ugandan training squad, ahead of the Cricket World Cup Challenge League fixtures in Hong Kong.
[12] In November 2019, Waiswa was named in Uganda's squad for the Cricket World Cup Challenge League B tournament in Oman.
[16] In November 2021, he was named in Uganda's squad for the Regional Final of the 2021 ICC Men's T20 World Cup Africa Qualifier tournament in Rwanda.