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

Yes

The meaning, grammar, and spelling of "fontes" are identical in both Brazilian and Continental Portuguese. The only difference is in pronunciation. In Continental Portuguese, the unstressed "e" at the end of the word is often almost silent or very swallowed (a very short, closed sound). In Brazilian Portuguese, the final "e" is typically more audible, even if it is slightly reduced.

Brazilian Portuguese Examples

1. "Eu sempre verifico as fontes antes de postar algo." (I always check the sources before posting something.)
2. "As fontes de água do parque estão secas." (The park's water sources are dry.)
3. "Eu prefiro fontes sem serifa para leitura digital." (I prefer sans-serif fonts for digital reading.)
4. "Ele precisa de novas fontes de renda." (He needs new sources of income.)
5. "As fontes de luz estavam bem fracas." (The light sources were quite weak.)

Continental Portuguese Examples

1. "É importante verificar as fontes desta notícia." (It is important to verify the sources of this news.)
2. "As fontes de água desta zona estão escassas." (The water sources in this area are scarce.)
3. "Eu prefiro utilizar fontes mais simples." (I prefer to use simpler fonts.)
4. "Ele possui diversas fontes de rendimento." (He possesses various sources of income.)
5. "As fontes de luz eram muito ténues." (The light sources were very dim.)