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

Yes

The word "encontrei" is identical in meaning, grammar, and spelling in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the vowels tend to be more open and melodic; the "en-" syllable is clearly nasalized, and the diphthong in "-trei" is pronounced with a more open, distinct sound. In Continental Portuguese, unstressed vowels are often "reduced" or swallowed, meaning the "e" in the first syllable might be almost silent, and the overall rhythm is more consonant-heavy and closed.

Brazilian Portuguese Examples

1. Encontrei meu celular no sofá. (I found my cell phone on the sofa.)
2. Encontrei um café muito legal aqui perto. (I found a very cool cafe near here.)
3. Encontrei meus amigos no shopping ontem. (I met my friends at the mall yesterday.)
4. Encontrei uma nota de vinte reais na rua. (I found a twenty-real note on the street.) Note: Brazilians frequently omit the definite article before possessive pronouns (e.g., "meu" instead of "o meu").
5. Encontrei o caminho rapidinho. (I found the way very quickly.)

Continental Portuguese Examples

1. Encontrei o meu telemóvel no sofá. (I found my mobile phone on the sofa.)
2. Encontrei uma esplanada muito gira aqui perto. (I found a very nice outdoor cafe near here.)
3. Encontrei os meus amigos no centro comercial ontem. (I met my friends at the shopping center yesterday.)
4. Encontrei uma nota de vinte euros na rua. (I found a twenty-euro note on the street.) Note: Portuguese people typically include the definite article before possessive pronouns (e.g., "o meu").
5. Encontrei o caminho rapidamente. (I found the way quickly.)