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

Yes

The spelling, meaning, and grammatical function of "coreana" are identical in both Brazilian and Continental Portuguese. The only difference is pronunciation. In Brazilian Portuguese, the vowels are generally more open and clearly articulated. In Continental Portuguese, unstressed vowels are often more closed or reduced, and the rhythm of the speech is more stress-timed, which alters the phonetic realization of the word.

Brazilian Portuguese Examples:

1. Eu adoro comida coreana. (I love Korean food.)
2. Ela é uma atriz coreana muito famosa. (She is a very famous Korean actress.)
3. A cultura coreana está fazendo muito sucesso aqui. (Korean culture is becoming very successful here.)
4. Minha amiga é coreana, mas mora no Brasil. (My friend is Korean, but lives in Brazil.)
5. Essa série coreana é muito legal. (This Korean series is very cool.)

Continental Portuguese Examples:

1. Eu adoro comida coreana. (I love Korean food.)
2. Ela é uma atriz coreana muito famosa. (She is a very famous Korean actress.)
3. A cultura coreana está muito na moda. (Korean culture is very trendy.)
4. A minha amiga é coreana, mas vive em Portugal. (My friend is Korean, but lives in Portugal.)
5. A música coreana tem muito sucesso entre os jovens. (Korean music is very successful among young people.)