I found some spelling and grammar errors on those three Virtual Boy covers.
Virtual League Baseball
The word "shagging" is misspelled on the back cover.
Teleroboxer
There is an incorrect word on the back cover. The sentence says "Automatically saves your progress at the end of each brutal march!" The last word should be "match". There is no marching in Teleroboxer.
Mario's Tennis
There is a mistake on the sentence "Enter a 3 round tournament to try to win the cup!" There are too many spaces between "3" and "round". Retype that text again and it will look right.
That's all I could find wrong with those three covers. I hope this helps you, e_brugal.