In Emerald, there is a small little addition into it. The gyms of Hoenn such as Rustboro, Dewford, Mauville etc. have all been spruced up a little bit
They have new trainers, with new Rostas at new levels

Updated Gym Sets in Emerald

Leader Roxanne
Rustboro City
Geodude Geodude Nosepass
Lv. 12 Lv. 12 Lv. 15

Leader Brawly
Dewford Island
Makuhita Meditite Machop
Lv. 19 Lv. 16 Lv. 16

Leader Wattson
Mauville City
Voltorb Electrike Magneton Manectric
Lv. 20 Lv. 20 Lv. 22 Lv. 24

Leader Flannery
Lavaridge City
Slugma Numel Camerupt Torkoal
Lv. 24 Lv. 24 Lv. 26 Lv. 29

Leader Norman
Petalburg City
Vigoroth Slaking Spinda Linoone
Lv. 27 Lv. 31 Lv. 27 Lv. 29

Leader Winona
Fortree City
Swablu Tropius Skarmory Pellipper Altaria
Lv. 29 Lv. 29 Lv. 31 Lv. 30 Lv. 33

Leader Liza & Tate
Mossdeep City
Lunatone Solrock Xatu Claydol
Lv. 42 Lv. 42 Lv. 41 Lv. 41

Leader Juan
Sootopolis City
Luvdisc Kingdra Sealeo Crawdaunt Whiscash
Lv. 41 Lv. 46 Lv. 43 Lv. 43 Lv. 41