This is the 6572nd most frequent French word.
internationaux
"Internationaux" means "international" (plural).
In this sentence, 'internationaux' describes agreements ('accords') as being of an international nature, indicating things that exist or apply between nations.
Les accords commerciaux internationaux sont essentiels pour l'économie.
International trade agreements are essential for the economy.
Here, 'internationaux' modifies 'compétitions sportives' to illustrate that these sporting events involve participants, teams, or audiences from multiple countries.
Les compétitions sportives internationales attirent beaucoup de spectateurs.
International sports competitions attract many spectators.
In this context, 'internationaux' applies to 'chercheurs' to signify researchers from multiple nations working together.