Item description:

This is a platinum save but the last skill has not been bought (similar to the US save). Just start a new story, get to an altar and buy the last remaining skill to get this trophy quickly (if you do not have any of the trophies for 1 and 15 skill points, they may unlock here as well). Also, If you play a story to its conclusion, you might get the trophy for all ending but I have no plan to test it myself. If you do, please let me know so I can add it to the post, thank you.

Most likely you will unlock other trophies as well such as those for the killings if you kill one of each enemy required, if you open a chest or destroy an object. No idea for the swords though. Since the trophy unlocks when you actually buy and upgrade them, you may need to that yourself (the same goes for gems and combos).