What are the separatist list that work at the moment? I heard about 'Double the fall', 'Triple Droideckas" and 'something with AAT'.
Could someone show me sample lists of that type and somehow describe how do they work? I am a new player, and separatists are rather new army so I cannot find many sources with gaming advice and tutorials for newbie

I only play casual but here is my list:

++ Standard (Separatist Alliance) [791 Points] ++

+ Commander +

•Count Dooku [240 Points]: Aggressive Tactics, Force Choke, Force Guidance, Force Push

•General Grievous [203 Points]: Aggressive Tactics, Endurance, •DT-57 "Annihilator"

+ Corps +

B1 Battle Droids [54 Points]: E-5C B1 Trooper

B1 Battle Droids [54 Points]: E-5C B1 Trooper

B1 Battle Droids [54 Points]: E-5C B1 Trooper

B1 Battle Droids [54 Points]: E-5C B1 Trooper

B1 Battle Droids [67 Points]: B1 Battle Droid, Integrated Comms Antenna, Radiation Cannon B1 Trooper

B1 Battle Droids [65 Points]: B1 Battle Droid, E-60R B1 Trooper, Integrated Comms Antenna

+ Command Hand +

Command Hand: •Fear, Surprise, Intimidation, •Trained in Your Jedi Arts, ••Double the Fall, ••Supreme Commander, •••Assault, •••You Disappoint Me, ••••Standing Orders

++ Total: [791 Points] ++

Created with BattleScribe (https://battlescribe.net)

basic strategy is rush dooku to the enemy as soon as possible, using force push to get them close and force choke to damage them a little. Take grievous alongside dooku, so once dooku is in melee, he can force push another unit into grievous so he can 'chop em up'. Keep the sniper droid (e-60r) back but in range 1 of an e-5c droid unit so they can chain orders. Could drop both extra droids, and both comms antennas for 2 hq uplinks on 2 of the e-5c units. Always make sure the droids are range 1 of each other and push with the rest of the droids.

Did you look 2 posts up at the post entitled "droid army builds"?

There's only 5 different unots at this point unless you got an AAT before everything got wrecked by coronavirus. So all the losts are going to look the same. Practice playing what you want til you figure out what works for you.