>>56614799I don't see where Espeon didn't catch on. Red had one in GS/HGSS along with Vee evolving into one in the manga as a major plot point of losing its omni-evolution superpower. Hell, in every instance I can think of Umbreon appearing, Espeon got just as much importance. The TCG whenever they push Umbreon we get a new Espeon card too, Mystery Dungeon paired them both together, Unite added Espeon even before Umbreon, Pokemon Colosseum had both front and center. Merch is pretty even with them too.
I think the closest is like, Gary in the anime having one? And placing slightly higher in some popularity polls, but even those vary wildly by region and timing.