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

No

While the spelling and grammar of "gatos" are identical in both Brazilian and Continental Portuguese, there are significant differences in meaning, usage, and pronunciation:

• Meaning/Usage: In Brazil, "gato" (singular) or "gatos" (plural) is widely used as slang to refer to illegal utility connections, such as "gato de luz" (an illegal electricity bypass). This meaning does not exist in Portugal, where the term "ligação clandestina" is used instead. Additionally, while both dialects use "gato" to mean a "handsome man," the word "bonito" is much more standard and common in Portugal.
• Pronunciation: The pronunciation of the "s" at the end of the word differs significantly. In most regions of Brazil, the "s" is pronounced as a simple [s] or, in Rio de Janeiro, as [ʃ] (sh). In Portugal, the "s" at the end of a syllable is almost always pronounced as [ʃ] (the "sh" sound).

Brazilian Portuguese Examples

1. Os gatos estão dormindo no sofá. (The cats are sleeping on the sofa.)
2. Aqueles caras são muito gatos! (Those guys are very handsome!)
3. Os gatos de luz são um problema nas cidades. (Illegal power connections are a problem in cities.)
4. Eu adoro brincar com os meus gatos. (I love playing with my cats.)
5. Os gatos pretos são muito fofos. (Black cats are very cute.)

Continental Portuguese Examples

1. Os gatos estão a dormir no sofá. (The cats are sleeping on the sofa.)
2. Aqueles rapazes são muito bonitos. (Those boys are very handsome.)
3. As ligações clandestinas de luz são um problema nas cidades. (Illegal electricity connections are a problem in cities.)
4. Eu adoro brincar com os meus gatos. (I love playing with my cats.)
5. Os gatos pretos são muito fofos. (Black cats are very cute.)