Could have sworn Soul Link is what it was called in Blue Moon and Red Sun...And CQC is short for Close-Quarters-Combat. Anyways, I'll work on a reason or something for the Cross System, though it's explained in the game itself that any Navi can use it so long as two navis are Link Navis.

EDIT: I lied, I went double cross, which I could have sworn was called Soul Link. Demon, can we do a bit of PMing to figure it out without straight up jacking the reason from Megaman himself?