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

Yes

The word "danço" is identical in meaning, spelling, and grammatical function (the first-person singular present indicative of the verb dançar) in both Brazilian and Continental Portuguese. The only difference is in pronunciation. In Brazilian Portuguese, the unstressed final "o" is typically pronounced as a clear [u]. In Continental Portuguese, while the final "o" is also often reduced to [u], the phonetic realization is influenced by a much more aggressive reduction of unstressed vowels and a different rhythmic cadence (prosody), which can make the word sound more "clipped" or "swallowed" to a Brazilian ear.

Brazilian Portuguese Examples

1. Eu danço muito bem no carnaval. (I dance very well during carnival.)
2. Eu danço samba com meus amigos. (I dance samba with my friends.)
3. Sempre que toca essa música, eu danço. (Whenever this song plays, I dance.)
4. Eu danço ballet desde pequena. (I have danced ballet since I was little.)
5. Eu danço muito nas festas. (I dance a lot at parties.)

Continental Portuguese Examples

1. Eu danço muito bem no carnaval. (I dance very well during carnival.)
2. Eu danço samba com os meus amigos. (I dance samba with my friends.)
3. Sempre que toca esta música, eu danço. (Whenever this song plays, I dance.)
4. Eu danço ballet desde pequena. (I have danced ballet since I was little.)
5. Eu danço muito nas festas. (I dance a lot at parties.)