In terms of distinct artworks there are just the three you’ve mentioned (assuming the first Shining Mew refers to the Shining Legends 40/73 one).
If you are looking for all variations of these cards, there are:
Three variations for the Japanese CoroCoro Shining Mew:
Seven variations for the Mew Gold Star of EX Dragon Frontiers:
- English
- English non-Holo from the Empotech Championship Deck of 2008- Japanese 1st edition
- Japanese unlimited edition
- German
- French
- Italian
Eight variations for the Shining Mew of SM Shining Legends:
- English
- Japanese unlimited edition
- German
- French
- Italian
- Spanish
- (Brazilian) Portuguese
- Korean
I’m pretty sure these are all, but maybe @lof102 or @skinst who both collect Mews know more?
Greetz,
Quuador