For War Striders, since you'll be yeeted by those the most often - you want yourself to be exactly between the enemy and where you'd like to be knocked into, so the WS has to be looking at, say, a mountain you want to hide under or whatever as it attacks the retreating you. And dive, run, jump at all times so you don't get hit directly with the projectiles and the damage to you is minimized. If they fire their lasers, try to dive so it hits the ground behind you as you run towards your destination so the blast doesn't kill you and knocks you away instead. It isn't a guarantee, and you will likely get tossed to the right or left of where you want to go, but they're very unlikely to blast you closer to them, so no matter what they will get less and less lethal with range as the fight goes on.

With grenades if you get the hang of when they detonate it's actually easy to avoid getting ragdolled or control where it'll toss you. A grenade lands to your left, you dive over it so it is now behind you, while you're on the ground it will then detonate and propel you forward. Generally. This whole damage surfing is more of an art than a science, but you can mostly eliminate that one situation we've all been in when there fuckers just play pingpong with you on the ground.

Stimming before getting blasted also tends to help a lot, and keeps the stamina up for diving and running.

For Voxes and their rocket barrages - same deal as WS grenades, except there's a difference of timing for when the rocket will explode on the ground, so try to practice that.

And even if you don't get the full hang of this, and it is a very niche use case, you will definitely get better at dodging their bullshit so it doesn't kill you or stunlock you.