You're gonna need to RNG your TID/ SID if you want reasonable shiny spreads for your legends in the 4th gen. Smogon has a guide about this on their forum.
I'm not entirely sure honestly.
Yeah I figured that for a new play through, but I've got the Enigma stone event Lati@s sitting on both games at the moment, so was going to see if there is a viable Shiny spread available to catch them before I restart. So can you use the battle video method to check SID's?
Also just been following the guide, going through the steps to see how it works (without TID/SID obviously) and decided to search for a HP Fire spread. It brings up a load but the natures are Impish, Mild or Gentle. The synchronise option is in the "Required Lead" box, but does this mean whatever Nature Sync'er I have it'll change to that nature?