Smash Bros Ultimate Tech "EZ Drop" (Ultimate's PC Drop)
EDIT: alright someone has already found it but the name for it was just "Instant ledge grab" and had no input viewer to show how to do it.
I'm not taking the ledge from anyone here so calling it ledge trumping isn't exactly correct either. I'm just trying to put name to tech that had just general terminology rather than specifics.
here are the creators of the videos about the PC Drop I stole
In order of appearance:
/ @thirdchair
/ mattdotzeb