>>48744712Easily HGSS because of the 8 Kanto gyms. Platinum has a better high level training area with Stark Mountain though.
I heard on the radio in HeartGold that there was a swarm of Chaney one day. So I set up a Butterfree with Compoundeyes at the front of my party, let it faint, and put a Stantler with Frisk and Thief behind it, then went to see the Chanseys. Compoundeyes increases the chance they have a held item, Frisk immediately tells me what the item is, and if it's a Lucky Egg I used Thief and then ran. I got 20 Lucky Eggs in a couple hours -- this was back when it was an item you're lucky to get even 1 of in a playthrough.
I traded a bunch of them over to Platinum along with pokes I wanted to level up. Stark Mountain + trade boost + Lucky Egg boost made for some very quick leveling.
