Character mistake: One of the other trainers said he rode over on a Pidgeotto, but it was a Pidgeot. (00:40:07)
Character mistake: When "If Only Tears Could Bring You Back" appears in the retyped ending credits of the English dub, Mewtwo Music is misspelled as "MewTwo Music" and "Newtwo Music" with courtesy misspelled as "couresy." Also, Lissome Music is misspelled as "lissome Music" with Connotation Music misspelled as "connotation Music." (01:13:33)
Character mistake: As Team Rocket discovers the cloning machine made by Mewtwo, they start naming the shadows of each Pokemon as they appear on the screen. As the first Pokemon appears on screen, they say "Alakazam" but it is actually an outline of "Scyther" who is a different type of Pokemon.
Suggested correction: As explained in the DVD commentary, Team Rocket don't know everything about Pokemon. They thought it was an Alakazam though.