What does the German say in the opening of ef - a tale of melodies?
It looks like the entire OP has been translated in this article. It says that the lines are from 2 different EF related songs, "Eternal Feather" from the ending theme of the last episode of "ef - a tale of memories" and "Emotional Flutter" from the opening of the game "ef - a latter tale".

The article has all of the text, side-by-side, with the English translation and (in red) the song that the line came from. There's also a note at the end about some names of other EF related songs on-screen.


  Holding the reviving memories [Eternal Feather]To my chest [Eternal Feather]There was a distant sky on the other side of the window [Eternal Feather]I was watching the unreachable clouds [Eternal Feather]The smile left behind on the road home, [Emotional Flutter]Will never find the voice it looks for [Emotional Flutter]The darkness engraved in my memories [Emotional Flutter]Even now, won't end [Emotional Flutter]Even now, won't end [Emotional Flutter]Swooping down from the sky, [Emotional Flutter]There was a distant sky on the other side of the window [Eternal Feather]I was watching the unreachable clouds [Eternal Feather]My breaking heart has been healed [Eternal Feather]I heard a tender voice [Eternal Feather]Pieces of a dream spill and fall into my palms [Eternal Feather]To search for the lost answer, I start running [Eternal Feather]Overcoming the time when we came across each other [Eternal Feather]Our hands join together [Eternal Feather]Holding the reviving memories [Eternal Feather]To my chest [Eternal Feather]I search for your back that I have forgotten about [Eternal Feather]Making the loneliness end [Eternal Feather]I believe you, but I feel uneasy [Eternal Feather]And I dreamed of your voice [Eternal Feather]I fear getting hurt [Eternal Feather]and make my face smile, [Eternal Feather]I'll start weaving a breakable courage, if we're together [Eternal Feather]When I change even the pain frozen onto me into warmth [Eternal Feather]The sound of the bell echoes [Eternal Feather]Into the endless future [Eternal Feather]Soar up high into the sky [Eternal Feather]Even if you don't have feathers [Eternal Feather]I believe you, but I feel uneasy [Eternal Feather]And I dreamed of your voice [Eternal Feather]The smile left behind on the road home [Emotional Flutter]Will never find the voice it looks for [Emotional Flutter]The darkness engraved in my memories even now, won't end [Emotional Flutter]Even now, won't end [Emotional Flutter]Swooping down from the sky, [Emotional Flutter]The white wings swayed [Emotional Flutter]Running with my outstretched hand, [Emotional Flutter]I chased after your shadow [Emotional Flutter]If the falling white snow were to pile up, [Emotional Flutter]It would cover up these sad colors [Emotional Flutter]The love sleeping deep within my heart [Emotional Flutter]Please remember it [Emotional Flutter]Soar high up in the sky [Emotional Flutter]And spread your wings [Emotional Flutter]Inside the gentle rays of the sun [Emotional Flutter]You showed me your dreams [Emotional Flutter]Fluttering down from the high sky, [Emotional Flutter]Wear your white wings [Emotional Flutter]Our joined hands [Emotional Flutter]Won't let go of the future [Emotional Flutter]The love sleeping deep within my heart [Emotional Flutter]Please remember it [Emotional Flutter]The smile left behind on the road home [Emotional Flutter]Will never find the voice it looks for [Emotional Flutter]The darkness engraved in my memories even now, won't end [Emotional Flutter]Even now, won't end [Emotional Flutter]There was a distant sky on the other side of the window [Eternal Feather]I was watching the unreachable clouds [Eternal Feather]My breaking heart has been healed [Eternal Feather]I heard a tender voice [Eternal Feather]Swooping down from the sky, [Emotional Flutter]The white wings swayed [Emotional Flutter]Pieces of a dream spill and fall into my palms [Eternal Feather]To search for the lost answer, I start running [Eternal Feather]Overcoming the time when we came across each other [Eternal Feather]Our hands join together [Eternal Feather]Holding the reviving memories [Eternal Feather]To my chest [Eternal Feather]Running with my outstretched hand, [Emotional Flutter]I chased after your shadow [Emotional Flutter]I search for your back that I have forgotten about [Eternal Feather]Making the loneliness end [Eternal Feather]