Phoebe (oras)

replacing the dusclops and one nanette could be done by:

shedninja
froslass

Bertha (DP)

She is sinnoh's ground type  her team has a sudowoodo (meaning false wood) replace it with
Torterra
Wormadam
Steelix
Gastrodon
Garchomp

Lance

He is really flying type in HG SS because all his pokemon

Aerodactyl (rock-flying)
Charizard (fire-flying)
Gyrados (water-flying)
Dragonite (Dragon-flying)
Dragonite (Dragon-flying)
Dragonite (Dragon-flying)
WHY IS HE FLYING TYPE

Agatha

She should have a cubone or marowack.

Bruno

In Red and blue he has a Hitmonchan, Hitmonlee, Machamp, and two Onix.  The two Onix could be replaced by Polywrath and a Primape.

In Gold and Silver he has a Hitmonchan, Hitmonlee, Machamp, one Onix, and a hitmontop.  The Onix could be replaced by a Polywrath.

Karen

The Elite 4's dark type member Karen from Johto has:

Umbreon (Dark)
Vileplume (Grass-Poison)
Murkrow (Dark-Flying)
Gengar (Ghost-Poison)
Houndoom (Dark-Fire)

see the problem?  2 aren't dark type, keeping with what they had at the time,  I would give her to replace Gengar and Vileplume, Sneasel (Dark-Ice) and Tyranitar (Rock-Dark).