I have made some save files with lots of help from the awesome save editor by Jappi88.
I made these saves after completing the game on the easiest difficulty, so I recommend you do the same. I don't know what other achievements these may pop.
These saves are primarily for getting the collectibles achievements and the Kleidos challenge achievements, as well as one for completing the story on the hardest (Prince of Darkness) difficulty.
For the achievement for completing the story on Prince of Darkness difficulty, I first played it on the easiest difficulty. I remembered to keep the last save file prior to the story ending. I then editted the file using Jappi88's editor and changed the save file to PoD difficulty. I then loaded it up and it worked. You may want to try it on your own if you don't want to use my save files. I certainly didn't want to play this stupid game for a second time with all the stupid 'stealth' sections, like that level with the stupid leaves, lol!
Achievement you will get in these save files are:
-Philanthropist (getting all art pieces)
-Customer of the Month (spending 20k at Chupacabra)
-Multiple Pockets (upgrade all relic slots)
-Void Collector (collect all Void gems)
-Life Collector (collect all Life gems)
-Chaos Collector (collect all Chaos gems)
-Expert Silversmith (collect all gems)
-Kleidos Champion I (complete the first set of challenges)
-Kleidos Champion II (complete the 2nd set of challenges)
-Kleidos Champion III (complete the 3rd set of challenges)
-Kleidos Champion IV (complete the 4th set of challenges)
-Kleidos Hero (complete all challenges)
-Kleidos Legend (complete all challenges on Prince of Darkness difficulty)
-The Outer Limits (get all collectibles, complete all challenges on PoD)
-Prince of Darkness (finish story on Prince of Darkness difficulty)
Let me know if there are issues with the save files.
Castlevania Lords of Shadow 2 achievement saves by OzQuant.rar