When we portray about the stylistic features, then we refer to figures of speech, which, in turn, are characterized by the alternatives available to the interlocutor in the sense of giving character to the messages he utters.
As it would not be possible to list them all here, let us focus on addressing only one - the apostrophe. It consists of the invocation, in the calling, of an interlocutor who is often absent in the act of enunciation, sometimes presenting himself as imaginary, fictitious. However, it is also worth noting that, as this is a fictitious aspect, this invocation can be directed to an inanimate being, a characteristic that is also present in another figure – the prosopopeia. However, the interlocutor can also be present, alive or dead, real or imaginary.
In this sense, as such manifestation occurs broadly in literary language, let us analyze some cases, one referring to the speech given by Castro Alves, in one of the famous creations he left us – Voices from Africa:
voices from africa
God! O God! where are you that you don't answer?
In which world, in which star do you hide
Concealed in the skies?
Two thousand years ago I sent you my cry,
What a bucket ever since infinity has run...
Where are you, Lord God...
[...]
We attest that the questioning takes place through the divine figure, clearly absent in the act of enunciation.
See now another creation by Fernando Pessoa, Portuguese sea:
O salty sea, how much of your salt
They are tears from Portugal!
Because we crossed you, how many mothers cried,
How many children prayed in vain!
[...]
We infer, therefore, that it is an inanimate receiver, portrayed by the figure of the sea.
But this stylistic feature can also address someone who is gone, as in Slaveship, by Castro Alves:
[...]
Arise, heroes of the New World!
Andrada! Tear down that banner of the air!
Columbus! close the door of your seas!
[...]
We note that here the call is addressed to Christopher Columbus.
Source: Brazil School - https://brasilescola.uol.com.br/gramatica/apostrofe-um-recurso-estilistico-linguagem.htm