Ok really simple, put you're bad agg in the first slot of you're party.
now put in this gameshark code:
[M] Must Be On
9266FA6C97BD
905B5ED35F81
B76A68E5FAB1

Copy Battled PKMN (Press L+R+Up. Copies PKMN to respective Party Slot)
Part 1/2
F67A165BE941
7F8A357FAC8B
92115E125F0F
30B5B539F648
72B935B15400
18491F87569B
C9BE 23BB2CBF
9EE1F785F6CF
BF5D89564DC0
D0D16A925689
2E827EAB24B0

Part 2/2
9D6B09767190
56817F91D697
49FA763D9C08
AE09AF90D64A
2D9F7EAF1CB0
108DAE906649
2CFF FE390C40
1E8CFF07465D
22C23C800543
180A5E5F7C1A
0F9FB63FBD12

Once the master code and battle copy code are on, go to grass,water, etc. Where every you
can find a pokemon to fight, once you found one press L+R+Up right befor you send out your pokemon,(it may take a few trys to get it right but it does work) now if done right you should throw out what ever pokemon you are
fighting(if you are fighting a wurmple you will throw out a wurple to fight as) once that
happens just run from fight,open up you're pokemon party and If done right You're bad egg
sould be gone and replaced with what ever pokemon you fought!
I have tested it and it works!
hope that helps =)