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

Yes

The word "bandeira" shares the same meaning (flag), spelling, and grammar in both Brazilian and Continental Portuguese. The only differences are in pronunciation:

• Brazilian Portuguese (PT-BR): The pronunciation is more open and melodic. The vowels are generally pronounced clearly and with more emphasis, and the rhythm is more syllable-timed.
• Continental Portuguese (PT-PT): The pronunciation is more "closed" and "reduced." Unstressed vowels are often shortened or almost disappear entirely, giving the word a more clipped, stress-timed rhythm.

Brazilian Portuguese Examples

1. A bandeira do Brasil é verde e amarela. (The Brazilian flag is green and yellow.)
2. Eu vi uma bandeira balançando no vento. (I saw a flag waving in the wind.)
3. Eles colocaram a bandeira no topo do mastro. (They placed the flag at the top of the mast.)
4. A bandeira da nossa escola é muito bonita. (Our school's flag is very beautiful.)
5. Preciso comprar uma bandeira para o desfile. (I need to buy a flag for the parade.)

Portuguese Examples

1. A bandeira de Portugal é muito bonita. (The flag of Portugal is very beautiful.)
2. Vi uma bandeira a abanar ao vento. (I saw a flag waving in the wind. Note: Portuguese people use "a + infinitive" instead of the Brazilian gerund "balançando".)
3. Colocaram a bandeira no topo do mastro. (They placed the flag at the top of the mast.)
4. A bandeira da nossa freguesia é azul. (Our parish's flag is blue. Note: "Freguesia" is a common administrative term in Portugal.)
5. Preciso de comprar uma bandeira para o desfile. (I need to buy a flag for the parade. Note: In Portugal, it is more natural to use "precisar de".)