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

Yes

The word "viagem" is identical in meaning, spelling, and grammatical function in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the unstressed vowel "e" is typically pronounced clearly as [i] or [e], and the final "m" acts as a nasal marker for the preceding vowel. In Continental Portuguese, unstressed vowels undergo significant reduction; the "e" in "viagem" is often shortened to a neutral "schwa" sound or becomes almost silent, making the word sound closer to "viag'm."

Brazilian Portuguese Examples

1. "Tenha uma boa viagem!" (Have a good trip!)
2. "Eu estou planejando uma viagem para o Rio." (I am planning a trip to Rio.)
3. "A viagem de ônibus foi muito cansativa." (The bus trip was very tiring.)
4. "Essa viagem vai ser muito legal." (This trip is going to be very cool.)
5. "Nós fizemos uma viagem incrível nas férias." (We took an incredible trip during the holidays.)

Continental Portuguese Examples

1. "Desejo-te uma boa viagem!" (I wish you a good trip!)
2. "Estou a planear uma viagem ao Porto." (I am planning a trip to Porto.)
3. "A viagem de autocarro foi bastante cansativa." (The bus trip was quite tiring.)
4. "Esta viagem vai ser muito fixe." (This trip is going to be very cool.)
5. "Nós fizemos uma viagem incrível nas férias." (We took an incredible trip during the holidays.)