Silica appears to be pretty decent pilot for this squad. You should place her in Lightning Mech, then power up Building Chain and her ability Double Shot. If you achieve that, you have to place Lightning Mech near structures, which have high probability of being attacked, and chain your double attack through them. If enemies moved unpredictably and you need to reposition your Lightning Mech, you can use Grappling Hook or push him with Rock Accelerator, to preserve its double attack.
It's nice to have Chen Rong or Archimedes piloting your Hook Mech. Ability to move after attacking gives you great opportunity to reposition enemies in correct places to chain Electric Whip attack through them, and after that move away, to avoid being hit. You can as well move away from the attack range of pulled enemies.
You can chain Electric Whip through your own mechs to reach more distant enemies. This is especially useful with the Hook Mech because of the Natural Armor.
Position your mechs carefully and in correct order, to avoid accidentally hitting them with Electric Whip. Care especially for squishy Boulder Mech, which can be one-shotted.
Giving Boulder Mech extra HP is helpful if you need to use its body to line up more enemies to attack with or if it's unavoidable, as any extra HP will prevent them from getting one-shotted.
Remember that mission objectives, deploys, and ally units are also damaged by Electric Whip. Because of that you should be prioritizing missions with objectives immune to it.
Without the Electric Whip, this squad lacks both damage and utility to complete missions, which makes positioning of your Lighting Mech critical. Avoid moving near the edge of the map and prioritize getting at least +1 move upgrade.
Boulders launched by the Boulder Mech can be used to block emerging Vek, chain Electric Whip attack through them or block enemy projectiles, it's basically your main utility source on this squad and you should treat it like so.