Okay this is a really minor one but I'm easily bugged by tiny, obscure things like this so:
Pokemon Crystal has a character called the Pokeseer, who will tell the player where they met their Pokemon and at what level, as well as how friendly it currently is. Later games just do this on the Pokemon's status screen but this was a primitive sort of version of that function. She can't tell where Pokemon which originated in, or have been in, Gen I came from as these games didn't have location data.
Anyway, if the player shows her a Pokemon from an event, or one obtained from Pokemon Stadium, she will say:
"What!? Incredible! I don't how understand how, but it is incredible! You are special. I can't tell where you met it, but it was at level <level>. Am I good or what?"
However, since the Virtual Console releases of the Gen II games had no event distributions and cannot connect to Pokemon Stadium, this dialogue string goes completely unused in those games. The only event Pokemon given out to the VC games was Mew, and as that was only to RGBY it won't work.
I guess you could trigger it if you did one of those complicated save-file transplants people have done to get Pokemon with Gen II event moves onto their Virtual Console save files, but that's beyond me.
Source:
https://bulbapedia.bulbagarden.net/wiki/List_of_locations_by_index_number_(Generation_II)