I think we'd need to see
MIKECALDWELL 's Sub-Zero vs
btbb99 or Jester's Raiden to get a good idea of how this matchup plays out at the highest level. These are two of my more underdeveloped fighters, but I still understand what needs to happen.
RAIDEN
His jabs will rip apart Sub-Zero... if you can get close to Subz. Shouldn't be too hard with Raiden's teleport. Don't jump too often. And when you're in close, try to avoid jumping backwards, as you might land in a freeze. Instead do jump-around kicks, because Sub-Zero likes to ground freeze when opponents are in close. If you can do the jump-around precisely, you can follow it up with a superman.
SUB-ZERO
As usual, Sub-Zero wants to stay far away. Slide, but not too much- Raiden can block and shock grab for a nasty combo. If you time it right, you can block the superman and freeze Raiden. You can also block it and jump kick him. Anticipate Raiden's teleports with uppercuts. Use the roundhouse to anti-air anytime Raiden tries to jump in at you.
I'd guess this is a 7-3 match for Raiden. But maybe the best Sub-Zeros have a winning strategy vs tough Raidens?
Raiden is great vs every fighter in MK2, but he is also beatable with every fighter, if you figure out the right strategy.