¿Esto suena natural? 暁のエレジーの後は「影の世界」しか残らない / "After the twilight's elegy, the only that remains is the "shadow's world"

Hello! I'm trying to write lyrics in japanese!
I hope you can help me.

This time, I want to translate:
"After the twilight's elegy, the only that remains is the "shadow's world"
暁のエレジーの後は「影の世界」しか残らない

An elegy is "A poem of serious reflection, typically a lament for the dead"
In spanish, if we usually use as title "Elegy for A" and it means "Aのエレジー" I think.
We give the name of what are we suffering for and give it the possession of the elegy in the title like "Elegy for my wife"

I think we use "for" like saying "It is still not yours, It will be yours until you hear it/recieve it".
Like when we say "This card is for you" instead "This card is yours"
Since an elegy is made for a dead, and a dead can't recieve the poem (can't hear) it will be "for" and never "of" in spanish or english thinking.
"For" shows destination to the person who will recieve it, I think.
So I thought maybe japanese will use の because your "present" and "future" are told different from us, so I think maybe の was ok for link the Person and the elegy and its possession.

In this situation "Twilight's elegy", as my translation to english from spanish, could mean that what I'm suffering is for the loss of the "twilight"".
"loss" can be interpretated as the "ending" of the twilight, that means the starting of the night. Figuratively, this could mean "After my suffering for the day becoming night" in a poetic way. But this is for spanish, I don't know if this is correct in japanese.

「影の世界」can have different meanings in spanish. In some way, it reffers to the night, the world where only shadows can habit (because there is not sun) even with light like moon or street lights, we see night as a very dark concept where shadows are. Another thinking is Plato's "Shadow world" and I know it's nonsense in some languages.
In spanish, we read "shadow world" the world that the "cave" represents in his Allegory of the Cave. Since the only think that the people in the cave could see were "shadows" we use the world "shadow world" when we can talk about the "shadows" plato's talked about, those things that aren't real, just the shadows of the real things (metaphysic things).
"Shadow world" can mean our physic world, this world without metaphysic things.
I tried to read articles about Plato in japanese, but it became hard because I couldn't recognize the concepts I know in spanish.
I write this because I wrote this trying to show two meanings, but apparently I will be able to show just one to japanese, am I right?
Maybe 影の世界 will be interpretated only in the way of "night" and it will be impossible to be interpretated as "Plato's shadow world" am I right? I just wanted to be very very sure about this.

Returing to grammar, I think "Aしか残らない" could mean "Just A remained" or "Anything remained but A"
This is because I want to say that "After twilight's elegy = After my lament of the day's ending" The only thing that remains is "The shadow world = The night"
Did I used it in the correct way or did I a mistake?

Also, I'm not 100% about the structure "Noun + の後は + action"
Can you tell me if I am wrong?

I hope you can help me, If I make any mistake, please tell me
Thank you so much.