Is Braille Alphabet universal, or is it specific and different for each language?

Braille – Wikipedia; English Braille – Wikipedia; Unified English Braille – Wikipedia

Braille is an encoding of alphabets; since the alphabetic repertoire is going to be different within Roman script, let alone other alphabets, there will be differences in the repertoire. Not all Braille alphabets will have a W, or a É, or a Ч. Moreover, Braille includes ligatures of letters and abbreviations; those are very much language-specific, depending on frequency within the language. The English character for <th> corresponds to the German character for <ch>, and the Albanian character for <dh>.

Ideally, each alphabet should have the same sign for A (or equivalent), B (or equivalent) and so forth, using phonetic correspondences where possible, and lining up with French Braille. So at least the core letters are meant to be the same. That has not always been the case, though it has become increasingly the case. American Braille, used until 1918, had not even half the same letters as French Braille in the alphabet.

The non-alphabetic characters of Braille, such as punctuation and symbols, have diverged even within English-language Brailles; hence the very recent adoption of Unified English Braille.

So the answer is no, although it has gotten better in the past century.