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

Yes

The meaning, grammar, and spelling of "escondido" are identical in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the vowels are generally more "open" and clearly articulated. In Continental Portuguese, unstressed vowels tend to be much more reduced or "swallowed." For example, the initial "e" and the "i" in the middle of the word may become very short or almost silent in certain Portuguese accents, whereas a Brazilian speaker will pronounce them more distinctly.

Brazilian Portuguese Examples

1. O gato está escondido atrás da cortina. (The cat is hidden behind the curtain.)
2. Eu achei um chocolate escondido na despensa. (I found a chocolate hidden in the pantry.)
3. Eles estão escondidos no quarto. (They are hidden in the bedroom.)
4. Não deixe seu brinquedo escondido aqui. (Don't leave your toy hidden here.)
5. Onde está o meu celular? Está escondido! (Where is my cell phone? It's hidden!)

Continental Portuguese Examples

1. O gato está escondido atrás da cortina. (The cat is hidden behind the curtain.)
2. Encontrei um chocolate escondido na despensa. (I found a chocolate hidden in the pantry.)
3. Eles encontram-se escondidos no quarto. (They are hidden in the bedroom.)
4. Não deixes o teu brinquedo escondido aqui. (Don't leave your toy hidden here.)
5. Onde está o meu telemóvel? Está escondido! (Where is my mobile phone? It's hidden!)