The load time is based on various things. If you have all Sheiks and Zeldas there is practically now load time at all. If there is just 1 Zelda, it'll take the maximum time to load. Even longer if there are other factors (game's loading a pokemon, AT, and say, Warioman all at the same time).
Actually, the amount of Zeldas and Sheiks doesn't really matter, I mean it does but it doesn't make loading faster. So if you have one Zelda and 3 Sheiks,(transforming from Zelda to Sheik) it won't make loading any faster than simply having one Zelda and one Sheik.
What does make loading faster is whether the Zeldas or Sheiks are the same colors as your Zelda and Sheik(you can have multiples of the same colors in online match or in team brawl).
I noticed this before and posted it here.
Here's why and how it happens.
If there is another Zelda or Sheik that is the same color as yours(except they're lighter or darker), you will transform nearly instantly(0.5 seconds).
So if you have a Red Zelda and a Red Sheik, if that Red Zelda transform to Sheik, she will transform nearly instantly.
Though there needs to be a Zelda(or Sheik) present in current game for the transformation to load faster/instantly. If you want to transform from Zelda to Sheik faster, there needs to be someone else playing Sheik currently(for example).
Though, this also occurs if there is a different colored Zelda. If there is a Red Zelda and a Blue Sheik, Zelda will transform about twice as fast as usual(about 1-1.5 seconds) but not instantly.
Kind of makes you wonder if the developers meant for Zelda to transform instantly.
Because I really don't see why they would base the transformation time on loading times, they should have made it a static time and preloaded both Zelda and Sheik in the match.
