What would Sceptile do I wonder?
Oak's ranch hasn't got that sort of jungle-like environment, and there aren't many rival Pokemon he would be sparring with, unless we see random trainer's Pokemon like Kabutops or Aggron somewhere...
As for Totodile, he does what he always has, dance!
Cyndaquil naps.
Snorlax naps, and EATS! I guess he's one of those Pokemon who are like "I'm bulking up for Football! (American, not Soccer)"
Bayleef, not entirely sure about her, I can't even remember what she was doing in that Chronicles episode.
Corphish is the only one really that I can see training, I'd say he spars with Kingler and Gary's Krabby.
Yeah, Bulbasaur's the designated leader of the ENTIRE ranch, so I'm sure calming down the Tauros herd and maybe some rampaging Nidoking/Kangaskan/whathaveyou is enough.