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

No

While the spelling, grammar, and literal meaning of "criança" are identical in both variants, the answer is "No" because there are differences in typical usage and pronunciation.

In Brazil, "criança" is the standard, everyday word used to refer to a child in almost any context. In Portugal, while "criança" is used in formal, medical, or literary contexts, the word "miúdo" (or "miúda") is much more common and natural in daily, informal conversation. Additionally, the pronunciation differs: Brazilian Portuguese features a more open, nasalized vowel in the syllable "an," whereas Continental Portuguese tends to reduce or neutralize unstressed vowels, making the final "a" sound much shorter and more closed.

Brazilian Portuguese Usage

1. A criança está brincando no parque. (The child is playing in the park.)
2. Eu era uma criança muito curiosa. (I was a very curious child.)
3. Aquela criança não para quieta. (That child doesn't stay still.)
4. Precisamos cuidar bem das crianças. (We need to take good care of the children.)
5. Ele trata todas as crianças com carinho. (He treats all children with affection.)

Continental Portuguese Usage

1. O miúdo está a brincar no parque. (The kid is playing in the park.)
2. Eu era um miúdo muito curioso. (I was a very curious kid.)
3. Aquele miúdo não para quieto. (That kid doesn't stay still.)
4. É preciso cuidar bem dos miúdos. (It is necessary to take good care of the kids.)
5. Ele trata todos os miúdos com carinho. (He treats all the kids with affection.)