Basics, upB and hold a direction, then press shield and hold the joystick pointing into the ground just as you would a wavedash to cancel.
To ledge stall press away from the ledge or down on the c-stick to fall and IMMEDIATELY upB and Zelda will regrab the ledge.
To practice the edgehog just go on ANY level and jump onto the ledge, then shield to roll on as usual. THEN, you will walk a step or two away from the ledge you rolled from and proceed to shorthop and teleport pointing the joystick diagonally towards the ledge you just came from. You do not need to do anything else and she should appear out of the full teleport and grab the ledge or if you do it perfectly she will just be on the ledge. This will help you figure out the spacing for ledgehogging from mid level. The spacing is approximately the same as the middle of the platforms on Pokemon stadium to the ledge as that is how I first got the spacing myself.
You can also be up in the air above the ledge(but inside the stage) and point it at a much steeper angle into the ledge.
You DO NOT need to jump, but it makes it easier usually(at least for me). It is possible to do it from stand and from platforms.