As shown here in the IL run I just submitted:

These are the 2 major strats:

• don't upgrade to Aerial Strike Level 2. The regular one is much better for both movement speed (Aerial Strike repeatedly) and combat (easier Tornado Throws which is strong and fast)
• wall splat properties are glitched in this game and Focus Aerial Throw Level 3 can exploit this by inflicting insane damage. The purple witch in particular has by far the highest health (4500), defense, and health recovery in the game (excluding immortal agents) and yet she dies in one throw, skipping one of the two fights completely

Also there are some minor optimizations here and there:

• save the fake red witch in the middle for a fast way to trigger the next cutscene, plus we get to damage our ally
• I use the Jackpot item upgrade to kill the red witch quicker
• killing the red witch saves time on unnecessary cutscenes, loading screens, and dialogues
• the first throw on the purple witch is for wall positioning reasons, the second one is for the kill
• you don't need to keep the focus ON for the entirety of a move that requires it; you can often just start a focus move and then stop focusing immediately, so the game has less slow motion
• reminder that the zoom reset button to quickly turn the camera around exists (would recommend to use during Aerial Strike)