This won't be a hack, it is just a plot I made up with name for it
I think a hack involving some legendaries is the ideal thing.
Heres a story off the top of my head.
You as a young trainer are embarked on a journey through the [region name here]. You come from [hometown here]. 50 years ago Professor Ross was a young pokemon researcher prodigy. After he came up with the solution to use time travel. Capture Dialga and command it to generate time travel. Professor Ross had methods to come face to face with Dialga but nothing seemed to work. Until he invited a lot of scientists from all over the world to see his science theory showcase. Where he invited many scientist to help him uncover Dialga to enable time travelling. As scientist joined, they became known as PokeX. PokeX became popular with over 500 scientists, and is still increasing rapidly in size. Finally, PokeX have a theory to summon Dialga. Some of the scientists believe the if finding red chain crafted by the once Leader of Team Galactic Cyrus they could summon Dialga face to face by dragging Dialga from the present dimension where it lives. PokeX scientists developed new Pokemon Brain Control devices big enough to accommodate pokemon the size of Dialga. It is up to you to stop PokeX from trying to use Dialga for time travel, PokeX had the theory of time drain and time manipulation. If they drain the molecules from Dialgas time travel abilities and copy the genetics forms of how it works that they can sacrafice Dialga in order to replicate time travelling. You must stop PokeX from sacarficing Dialga for Time Travel!