You are both right it can be organized. Already have some ideas.
Cool. I'd be interested. One idea to keep in mind when organizing such events, there are many historical cultures represented in the MO2 universe. Most of them have their own traditions of martial sports/festivals. A traditional knight tournament seems like something that would be a modern invention of Tindremenes. So it would make a lot of sense to run such an event. But you could do different events with different cultural themes, or even melting-pot events that draw different competitions from many cultural themes.
Themes you could include:
Post-Rome European Medieval (Tindremic)
Roman Inspired Events (Traditional Tindremic)
Persian/Arabic (Sarduucan)
Mongolian/Japanese (Khurite)*
Vikings (Kallard)
Sub-Saharan Africa (Sidioan)**
Unique MO2 Cultures (Ohgmir/Alvarin/Risar-Thursar)
*I included Japanese as the more I look at Khurites the more I realize they are a mix of the two cultures. Particularly in weapons, you see some massive Japanese influence on Khurites in the form of katanas, nodachis, and asymmetrical bows. As steppe nomads they definitely draw more inspiration from the Mongolians, but events inspired by Japanese culture would not be at all out of place.
**Sub-Saharan Africa includes a huge range of cultures. Without commentary from developers, it could be hard to narrow down which particular ones the Sidoians bear the most resemblance to, but if you're looking in particular at large/organized kingdoms, the Malians and Ethiopians would be two good cultures to look at. Sidoians are an ex-slave race though so you might be able to reason incorporating elements from many sub-saharan African cultures if we assume they were not all taken from the same people.
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Based on the above, you could include elements such as unarmed combat, throat singing, chariot (cart) racing, etc based on the many historical influences of the game. Beyond the fact that Ohgmir/Alvarin/Risar culture and the fantasy setting of the game, in general, give you a lot of liberty to straight make stuff up. For instance, in a setting with magic we could only assume some events would arise that include it's usage. Also Alvarins would be a great way to include some mezo-American events given their similar homeland.