The version on SWG is not updated yet.
I think maybe the summary needs a tweak, but I'm not sure what to add.
Such Great Deeds (12619 words) by Himring
Fandom: The Silmarillion and other histories of Middle-Earth - J. R. R. Tolkien
Rating: Teen And Up Audiences
Warnings: Major Character Death
Characters: Beleg, Fingon, Mablung, Círdan, Gwindor
Additional Tags: Friendship, Cross-cultural, Noldor - Freeform, Sindar, Grief/Mourning
A friendship fic featuring Beleg and Fingon, from the Mereth Aderthad to the Dagor Nirnaeth Arnoediad.
With various guest appearances and a great deal of conversation on a number of different subjects.
The stand-alone version just featuring Beleg and Mablung immediately after the Nirnaeth is called "Even So the Reeds Hissed in Serech at Sunset" and is here:
It's also cross-posted to Many Paths to Tread.
Thank you very much to everyone who has already found either of these and commented!
I'm behindhand with comments and replies, but hope to catch up soon.