Lex may seem extremely weak against Tyra, but when you have no mobility against a flanker there are plenty of situations where you could be caught off guard. When countering Tyra, Combat Slide (and the Heroism legendary) is the way to go.

It’s hard to escape a good Skye. However, she has no mobility aside from movement speed, so if one jumps out at you, Flutter straight up and flick down shots on her before she can lock on again. Use Seedling if available.

As I said in my Willo vs. Kinessa tip, play carefully and keep moving. As a continuation of that tip, keep Flutter on as low of a cooldown as possible. You can also use your ultimate as a distraction play if necessary.

Because Torvald can no longer drain shields your ability to specifically counter him has been significantly decreased. However, you have Nullify on your side, as well as a decent DPS - don't hesitate to fight fire with fire and get into close combat.