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

Yes

The word "empresa" is identical in both Brazilian and Continental Portuguese in terms of meaning, spelling, and grammatical category. The only difference is pronunciation. In Brazilian Portuguese, the vowels are generally more open and clearly articulated. In Continental Portuguese, unstressed vowels (such as the initial "e") are often reduced or "swallowed," making the word sound much more clipped and the first syllable much shorter.

Brazilian Portuguese Examples:

1. Eu trabalho em uma grande empresa. (I work in a large company.)
2. A empresa está contratando novos funcionários. (The company is hiring new employees.)
3. Ele abriu sua própria empresa no ano passado. (He opened his own company last year.)
4. Essa empresa é muito famosa por aqui. (This company is very famous around here.)
5. A nossa empresa tem um ótimo plano de saúde. (Our company has a great health plan.)

Continental Portuguese Examples:

1. Eu trabalho numa grande empresa. (I work in a large company.)
2. A empresa está a contratar novos funcionários. (The company is hiring new employees.)
3. Ele abriu a sua própria empresa no ano passado. (He opened his own company last year.)
4. Essa empresa é muito famosa por cá. (This company is very famous around here.)
5. A nossa empresa tem um ótimo plano de saúde. (Our company has a great health plan.)