Is the word evento the same in Brazilian and European Portuguese?

Yes

The word "evento" is identical in spelling, meaning, and grammatical function in both Brazilian and Continental Portuguese. The only difference is pronunciation. Brazilian Portuguese tends to have more open, clear, and melodic vowels. In contrast, Continental Portuguese is characterized by significant "vowel reduction," where unstressed vowels (such as the "e" in the middle of "evento") are much more closed, shortened, or almost neutralized, making the word sound more "clipped."

Brazilian Portuguese Examples

1. O evento de hoje vai ser muito legal. (Today's event is going to be very cool.)
2. Eu estou organizando um evento para a empresa. (I am organizing an event for the company.)
3. Teve um evento importante na rua ontem. (There was an important event on the street yesterday.)
4. Você vai participar do evento de amanhã? (Are you going to participate in tomorrow's event?)
5. Um evento estranho aconteceu durante a festa. (A strange event happened during the party.)

Continental Portuguese Examples

1. O evento de hoje vai ser muito fixe. (Today's event is going to be very cool.)
2. Estou a organizar um evento para a empresa. (I am organizing an event for the company.)
3. Houve um evento importante na rua ontem. (There was an important event on the street yesterday.)
4. Vais participar do evento de amanhã? (Are you going to participate in tomorrow's event?)
5. Um acontecimento estranho aconteceu durante a festa. (A strange occurrence happened during the party.)