Its not possible to get it legal
Instant you can try to find someone who already has a mew and you'll could obtain it from Pal park that way.
No, there is no legitimate Action Replay code for Mewthree for Pokemon Diamond.
You can't possibly catch latios in Pokemon diamond although you may get it there by using your ruby version if you have one to import it to your diamond. another way is to buy an action replay and cheat
You can only find it using an item you get from a Nintendo Event or using Action Replay.
Use the code on an action replay
You cannot catch totodile, chikorita, or cyndiquil without migrating.
ye you can
Catch trainer Pokemon
Mewthree cannot be caught in Pokemon Diamond, even with an Action Replay, because it does not exist in the game's data.
if its action replay than look up action replay codes on google
trade or migrate or action replay
You can't.
No you cannot.
not without an action replay and a Pokemon modifier code.
get an action replay, get the Pokemon modifier cheat for it, then catch all the Pokemon.
No, there is no legitimate Action Replay code for Mewthree for Pokemon Diamond.
You can't unless you have an Action Replay Ds
you use the ds action replay or you migrate it