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

No.

The word usa is the third-person singular conjugation of the verb usar (to use). While the meaning, spelling, and grammar of the word itself are identical in both dialects, there is a difference in typical usage regarding how people are addressed. In Brazil, usa is the standard conjugation used when addressing someone directly (via the pronoun você). In Portugal, the second-person form usas (paired with tu) is the natural way to address someone informally; using usa to address a person in Portugal is typically reserved for the third person (he/she) or for very formal, distanced address. Additionally, the vocabulary used alongside the verb often changes (e.g., celular vs. telemóvel).

Brazilian Portuguese

1. Você usa muito esse perfume. (You use this perfume a lot.)
2. Por que você não usa o casaco? (Why don't you use the jacket?)
3. Ele usa o celular o dia todo. (He uses the cell phone all day.)
4. Ela usa óculos para ler. (She uses glasses to read.)
5. Você usa redes sociais? (Do you use social media?)

Continental Portuguese

1. Tu usas muito esse perfume. (You use this perfume a lot.)
2. Por que não usas o casaco? (Why don't you use the jacket?)
3. Ele usa o telemóvel o dia todo. (He uses the mobile phone all day.)
4. Ela usa óculos para ler. (She uses glasses to read.)
5. Tu usas redes sociais? (Do you use social media?)