Well, well. D&P series has done another fresh idea I hope they'll do. Hopefully they don't blow it by having the new girl appear once instead of Hikari's ongoing rival.
Our hopes have come true. Hikari's rival is a girl. Now the only thing to do is sit around and wait until she shows up in an episode.
Is Hikari's new rival thinking of the romance from Ash and Hikari?
It really depends on how the writers would do as romance come and go in the entire Pocket Monsters series. If Sato for some reason enters a Contest, I'd say yes. Otherwise, it may not be likely.