It is an attempt to give her name a French spelling and pronunciation. English does not have that letter é in the alphabet.
In her case, e' (or é) is pronounced as a separate syllable, as "ay". It does not mean that the syllable gets an accent.
The name was derived from her mother's maiden name, Biyancé
Where is Beyonce from?
There is an apostrophe on the last letter 'e' in "beyonce.' in a text book? Whay is that?
2 answers
She is from Houston, Texas, USA.