Diane and Butler? Any married couple?
I guess they don't count because they're OLD PEOPLE. xD
Well, we have canon one ways such as
Rudy -> Misty
WhatshisfacefromChronicals -> Misty
Conway -> Dawn
Angie -> Ash
Haha I mean ones that 1) Are 2-sided [they don't even have to be simultaneous, just the same 2 people liking each other at some point] and 2) not a COUPLE couple. Like, not together when we meet them. And 3) preferably main characters or secondary ones (who'd be like Zoe, Kenny, Barry, Paul-- anyone we see a lot but not every episode). Tertiary characters (- of the day, or in only a couple episodes like a story arc) don't really count because either it just wouldn't happen or it would be taken for granted (there'd be no time for character development).
One-ways, even though they are shippy when we come across them, in the long run feel flat. Like, I doubt we're going to see Misty and Rudy together in the future, or that Angie will come back and somehow convince Ash that he loves her. If something like that did happen, it'd feel strange, abrupt, and like a let-down. One-ways are for mild amusement, but if we never see two-way development, then I don't think there's much stock in them.
Sorry this is long. I just think it's peculiar. Like, they have so many main characters they could be dealing with without risking ruining the whole show, and MayXDrew was the closest we ever got. Which was, not close at all. In fact, so many shows seem to draw people in BECAUSE of the relationship stuff that isn't even happening but is hinted at that COULD happen, yet Pokemon has rarely taken advantage of that audience characteristic. I'm not even saying there HAS to be one, because a random pairing for the sake of it might be cheesy, awkward, and slow the show down. It's just peculiar.