| Link | Location |
|---|
 | Ivie Osobase | Live online from Sydney, Australia |
| Maciej Ossowski | Starogard Gdanski, Poland |
| Magdalena Ostalska | Warszawa, Poland |
| Alena Ostanina | Astana, Kazakhstan |
| Devin Osterhout | Salt Lake City, Utah, United States |
| Amanda Österling | Warsaw, Poland |
| Aleksandr Ostroukhov | Saint-Petersburg, Russia |
| Andrzej Ostrowski | Wrocław, Poland |
| Franciszek Ostrowski | Rzeszów, Poland |
 | Alberto Osuji | Lagos, Nigeria |
| Joe Oswald | Columbus, Ohio, United States |
| Yuki Otsuka | Tokyo, Japan |
| VADIM OTTO | Moscow, Russia |
| 大内一季 | Tokyo, Japan |
| Kenichiro Ouchi | Tokyo, Japan |
