Brazilian Portuguese and European Portuguese are not exactly the same language, but they are not that different either!
There are a few minor changes in Brazilian Portuguese, but Brazilian Portuguese is not a Portuguese creole, as both languages have the same grammar and vocabulary as traditional Portuguese.
That being said Brazilian Portuguese has evolved slightly differently due to cultural and historical differences and some would compare the differences between Brazilian Portuguese and European Portuguese to the way British and American English are different from each other.
Others argue the differences between the two languages are more substantial. This is why when commissioning Brazilian Portuguese transcriptions we would always recommend using a native-speaking transcriptionist to ensure local understanding of the subtle differences between the two languages to get absolute accuracy.