I did the spider matriach by accident at lvl 3 cause I didn't know this area and was surprised.
You can by antidotes/poison elixirs to negate a stupid amount of damage (which I didn't do/only super late into the fight) and just chugged or threw healing potions around.
With enough healing potions you shouldn't struggle at all especially if you play the fight smart and abuse the bridges & destroy the eggs with alchemistic fire etc.
I only played the EA so I don't know all of the options, but you could in general clear the forest, clear the swamp, do the goblin camp/castle, deal with the Gnolls, help the people in the burning buildings, in general explore the world.
You did a decent amount but still have TONS of stuff to do around you before you would ever have to think about dealing the spider matriach rn
