Choose the "Setting" option at the hangar. Then choose the "Auto Save/Password" option and enter one of the following passwords to activate the corresponding cheat function.

All Zentradi Arms EX mission
Enter EHIAR as a password.

Do You Remember Famitsu? EX mission
Enter LAMGV as a password.

Super Dimension Gladiators Dengeki EX mission
Enter IGYSU as a password.

Generation Drive EX mission
Enter KSALE as a password.