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

No

While the fundamental definition of "tias" (the plural of tia, meaning aunts) remains the same in both dialects, there is a significant difference in typical usage. In Brazil, "tia" is often used as a social term of endearment or a way to address older women who are not biologically related to the speaker (such as a family friend, a neighbor, or even a shopkeeper). In Portugal, the use of "tia" is much more restricted to actual family members; addressing a stranger or an acquaintance as "tia" would be considered highly unusual or even impudent.

Brazilian Portuguese Examples

1. Minhas tias vão me visitar no domingo. (My aunts are going to visit me on Sunday.)
2. Eu amo as minhas tias. (I love my aunts.)
3. A tia da padaria é muito simpática. (The lady at the bakery is very nice.)
4. Minhas tias estão fazendo um bolo. (My aunts are making a cake.)
5. Vou pedir ajuda para as minhas tias. (I'm going to ask my aunts for help.)

European Portuguese Examples

1. As minhas tias vêm visitar-me no domingo. (My aunts are coming to visit me on Sunday.)
2. Eu adoro as minhas tias. (I adore my aunts.)
3. A senhora da padaria é muito simpática. (The lady at the bakery is very nice.)
4. As minhas tias estão a fazer um bolo. (My aunts are making a cake.)
5. Vou pedir ajuda às minhas tias. (I'm going to ask my aunts for help.)