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

No

While the spelling and meaning of "sanduíche" are identical in both Brazilian and Continental Portuguese, there are differences in grammar and typical usage. Grammatically, the gender of the article used with the word differs: in Brazil, it is typically masculine (o sanduíche), whereas in Portugal, it is typically feminine (a sanduíche). Additionally, there are differences in typical usage regarding the vocabulary used to describe the ingredients or similar items (e.g., using fiambre instead of presunto, or tosta instead of sanduíche for pressed sandwiches).

Brazilian Portuguese Examples

1. Eu quero um sanduíche de presunto e queijo. (I want a ham and cheese sandwich.)
2. Você prefere sanduíche natural ou quente? (Do you prefer a cold sandwich or a hot one?)
3. Fiz um sanduíche para o lanche. (I made a sandwich for a snack.)
4. Esse sanduíche está muito recheado! (This sandwich is very stuffed!)
5. Adoro comer sanduíche no parque. (I love eating sandwiches in the park.)

Continental Portuguese Examples

1. Queria uma sanduíche de fiambre e queijo. (I would like a ham and cheese sandwich.)
2. Vou comer uma tosta. (I am going to eat a toastie.)
3. Fiz uma sanduíche para o lanche. (I made a sandwich for a snack.)
4. Esta sanduíche está muito boa. (This sandwich is very good.)
5. Queres uma sanduíche ou um prego? (Do you want a sandwich or a steak sandwich?)