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

No.

While "caras" shares the same literal meaning (the plural of cara, meaning "faces") and the same adjectival meaning (the plural of cara, meaning "expensive") in both dialects, it is not the same in terms of typical usage. In Brazilian Portuguese, "caras" is a very common informal way to refer to "guys" or "dudes." In Continental Portuguese, this usage is not used; instead, people use "gajos" to refer to individual men or "malta" to refer to a group of people.

Brazilian Portuguese

1. Esses caras são muito legais. (Those guys are very cool.)
2. Não gosto de caras folgados. (I don't like cheeky guys.)
3. E aí, caras, tudo certo? (Hey, guys, is everything alright?)
4. Essas roupas são muito caras. (These clothes are very expensive.)
5. As caras deles estavam assustadas. (Their faces were scared.)

Continental Portuguese

1. Esses gajos são muito fixes. (Those guys are very cool.)
2. Não gosto de gajos folgados. (I don't like cheeky guys.)
3. Olá, malta, tudo bem? (Hello, guys/folks, is everything okay?)
4. Estas roupas são muito caras. (These clothes are very expensive.)
5. As caras deles estavam assustadas. (Their faces were scared.)