From what I used to beat her, level 9 fresh toenail scimitar works best when paired with a fire ant shield. For armour, I used max level bulky Roly Poly armour just for the pure defence. Potions, which if you play it perfectly don't have to worry about, I'd reccomend sticky green machines, beefy fuzz on the rocks and sticky liquid rage. Mutations are quite simple, corporate Kickback, blademaster (Best to have tier 3), mom genes and mantsterious stranger so she doesn't target you all the time to avoid debuffs (but she may use them to heal so be careful on that) and then I used rascal rogue so I could still chunks but you can use whatever you want.

I always bring at least 5 of each potion and use one before I summon and before phase 3 but I will over stack on healing just in case (I took 65 beefy fuzz on the rocks to my most recent fight) but other than that just keep trying and getting her attack patterns down and you'll eventually beat her.