I don't think she'll confess cause there will be no pairing till maybe at the end of the series.
Think about it, they want to keep the fans who'll pair every new girl to be with Ash through his adventures, so they don't want to lose the next ship coming up which is Ash and Lillie. If Serena confesses, she'll be rejected. They won't do that to her. It be will good byes, thank you and alike every character leaving Ash.
If you want Ash and Serena to be together, you'll have to want Ash keeping the handkerchief. It will give a kind of a push for the ship.
If the producers want to show something related to Serena, they have the option of the handkerchief. It's a good thing cause she will somewhat rival Misty with the things she gave him and were shown throughout the series. Sorry about that, but I must say Misty has much more possibility to be with Ash if they ever wanted a pairing.
I know I know. I'm a troll, but I like to tease about Misty 
that only works for ash and misty because it is her hankerchief that she gave to ash in a romantic gesture, with this it is still ash's hankerchief, not serena's so I don't see how you could twist it around like that.
lol nice trolling though xD
they'll brush off that moment too acting like its 4kids's doing like usual though
(even though it isn't and is from the japanese version since giving a guy a hankerchief is a japan thing, something 4kids would have no idea about, but they'll use the excuse anyways...),
so don't waste your time trolling
Edited by ultranx, 18 September 2016 - 02:12 AM.