That would actually be pretty amazing. So each character would basically get their down special from Smash 4? I know Zero Suit Samus is in dire need of a more original up special, but I'm not sure if it's the safest thing to just simply copy Smash 4 all day.
I've been thinking of what to give them in place of the old down-special (that's been moved), and while Bouncing Fish (Sheik) may be possible to recreate in PM, I don't know about Phantom Slash (Zelda).
So in that regard, I would give Zelda this:
This is what I call a "Magic Counter".
Using Down Special on a projectile/the opponent would function more like Mario's Cape only using Light magic (but hits on both sides of her and does no damage).
But when used on an incoming attack much like a counter, it would use Dark Magic and deal around half the damage back to the opponent.
If used in the air/on an airborne opponent it would spike them (if it hits the sweet spot of the move) using electric magic.
Then Sheik would get this:
This is what I call "Sheikah Sly".
Using the similar situations as above for zelda, the move would do the following:
On projectiles and opponents, you would bounce off of them (and if it's a projectile, destroy it).
If used like a counter on an incoming attack, you would bury your opponent.
If used in the air/on an airborne opponent you will do a command throw that involves a deku nut of sorts.