I don't think there's an editor, at least none that I know, but I know where the data is located in the save file, if that helps.
It's in save section 4.
0x250 - 0x253 Actual IVs of the Pokemon? (due to that roamer glitch only the first byte from here is used during encounter)
0x254 - 0x257 PID
0x258 - 0x259 Species