Is there any Preparation Guide for
1Z0-419(Oracle Application Development Framework 12c Essentials) Preparation Guide?
Unfortunately not that I can find (and I don't count the, "no pun intended", COUNTLESS of illegal brain dumps from websites claiming to have the questions and answers).
As this exam is not as popular where there are study guides, it is popular enough that there are lots of brain dumps.
Remember, if somehow Oracle determines that you studied from a brain dump, your exam results will be invalidated and you could be suspended from the Oracle Certification program and if you have any existing certifications, they may be revoked.