for me it reminds me a lot of Spanish, because Portuguese and Spanish are the two largest branches that have emerged from the Romance languages.

When I didn't speak any Russian, yes, Portuguese, even the one spoken in Brazil, sounded like what I imagined Russian to be. Now, the language spoken in Brazil doesn't sound anything like Russian to me. Totally different intonation, rhythm and many sounds that they don't share. As for the one spoken in Portugal, sure, there are one or two similar sounds in Russian, but I wouldn't go so far as to say European Portuguese sounds like Russian or other Slavic languages.

I don't really think Portuguese sounds like French either. French doesn't sound like any of the other Romance languages to me, except sometimes, maybe, Catalan.

As a native Brazilian Portuguese speaker, I believe Brazilian Portuguese sounds like Latin American Spanish. I believe all the immigration between Portugal and Spain to Latin America in the 1500’s may have affected both languages in that area to sound alike.

But a Polish can read a writing in Portuguese and Brazilian natives understand what he is talking, even if he does not even know what he is saying.