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

Yes

The spelling, meaning, and grammatical function of "interesse" are identical in both Brazilian and Continental Portuguese. The only difference lies in pronunciation:

• Brazilian Portuguese: The final "e" is typically pronounced as a clear, unstressed [i] sound (similar to the "ee" in "see").
• Continental Portuguese: The final "e" is much more reduced and "closed." It is often pronounced as a near-silent, very short [ɨ] sound, making the word sound much shorter to a Brazilian ear.

Brazilian Portuguese Examples

1. Eu não tenho nenhum interesse em política. (I have no interest in politics at all.)
2. O seu interesse por música é muito grande. (Your interest in music is very great.)
3. Eles demonstraram interesse na nossa proposta. (They showed interest in our proposal.)
4. Tenho muito interesse em aprender novos idiomas. (I am very interested in learning new languages.)
5. Qual é o seu interesse nesse projeto? (What is your interest in that project?)

Continental Portuguese Examples

1. Eu não tenho interesse nenhum em política. (I have no interest at all in politics.)
2. O teu interesse pela música é muito grande. (Your interest in music is very great.)
3. Eles demonstraram interesse na nossa proposta. (They showed interest in our proposal.)
4. Tenho muito interesse em aprender novos idiomas. (I am very interested in learning new languages.)
5. Qual é o teu interesse neste projeto? (What is your interest in this project?)