I Do Believe In Magic
Summary: Based on this post. AU 5x09 flashback, in which present day Oliver Queen actually time-travels back for a short visit to see Felicity in 2012, before she became his partner, before he’s supposed to be in love with her.
Also on AO3.
STAR CITY, 2016
Oliver Queen stood stiffly before the computer called Gideon, watching as Nate Heywood hit a sequence of neon buttons that didn’t mean anything to him. Unknowingly, his thumb and index finger rubbed together anxiously at his side. The longer he waited, the more cracks began to form and spread like weeds through his chest, weakening his resolve.
“Are you sure this is the time you want to go to?” Nate stopped typing and glanced at him with concern.
Oliver swallowed once. No. He wasn’t sure at all.